UNIVERSITY  OF  ILLINOIS 
LIBRARY 


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Volume 

vr\ 


Ja  09-20M 


AlTGEll)  HAtL  STACKS 


UNIVERSITY  OF  ILLINOIS 
LIBRARY 


Class 


Book  Volume 


Ja  09-20M 


MANUAL  OF  INSTRUCTION 


IN 

FORGE  AND  MACHINE  WORK, 


With  Figured  Drawings  of  Methods  and  Exercises 
Used  in  the  Fowler  Shops  of 
Kansas  University. 


By  FRANK  E*  WARD, 


Superintendent  of  Fowler  Shops  and  Shop  Instrue 
tion,  Instructor  in  Machin^Work  and 
Mechanical  Methods  ancf  Practi^. 


Copyright  1901  by 

Hudson-Kimberly  Publishing  Co., 
Kansas  City,  Mo. 


'\AiVT.eele.f  ^ ~ ' 


0 


INTRODUCTION. 


This  little  book  outlines  the  student’s  actual 


/ork  in  the  Fowler  Shops  of  the  University  of 
lansas.  It  is  written  by  a practical  mechanic,  trained 


formerly  Superintendent  of  the  Bates  Machine  Com- 
pany; it  is  written  in  the  spirit  and  language  of 
the  machine  shop ; it  is  written  after  a twelve-years 
experience  with  young  men  in  this  University. 

The  Fowler  Shops  were  founded  for  two  pur- 
poses. First:  To  train  young  engineers  in  correct 

inethods  of  machine  practice.  Second  : To  develop 

the  individual  manual  skill  nece^ssary  for  the  modern 
engineer.  It  is  the  purport  of  this  book  to  outline  a 
method  to  accomplish  both. 

It  is  not  the  only  method,  and  perhaps  not  the 
best,  but  it  has  proven  a successful  method. 

With  this  brief  introduction,  I desire  to  express 
my  appreciation  of  Mr.  Ward’s  ability  and  his  consci- 
entious instructorship  of  young  men. 


the  rolling-mills  and  machine  shops  of  Joliet,  and 


cT 


Lucien  I.  Beake, 
Director  Fowler  Shops. 


3^- 


PREFACE. 


After  twelve  years’  experience  as  instructor  in 
forge  and  machine  work,  and  with  previous  training 
in  practical  work  as  machinist  and  foreman  of  machin- 
ists, the  writer  is  prompted  to  put  this  book  in  print 
for  four  reasons  : 

I.  To  place  in  book  form  the  various  blue-prints 
and  sketches  which  have  been  used  and  approved  as 
the  most  desirable  course  to  give  on  the  subjects 
named,  and  these  arranged  to  conform  with  the  lim- 
ited time  which  the  student  has  for  work. 

II.  To  give  in  written  form  much  general  instruc- 
tion which  otherwise  must  be  verbal. 

III.  To  show  the  application  of  each  step  in  the 
work,  and  to  give  other  similar  methods  that  could  be 
used  under  varied  conditions. 

IV.  To  produce  a well-bound  pocket-book,  to  be 
carried  by  the  student  to  the  shop  or  room  for  refer- 
ence, so  that  all  may  be  well  prepared  to  work. 


6 


MAmAL  OF  INSTRUCTION  IN 


Shop  Ethics* 

The  first  and  most  important  lesson  for  the 
beginner  is  to  learn  to  work  harmoniously  with  others, 
who  have  equal  rights  and  privileges.  And  the  fol- 
lowing suggestions  will  help  those  who  try  to  do 
right. 

I.  Talk  but  little,  and  only  about  your  own 
work.  Pass  no  remarks  about  others'  troubles  and 
take  no  special  notice  of  them,  unless  requested. 

II.  Borrow  no  private  tools  and  be  neat  and  con- 
siderate with  the  tools  for  general  use,  Check  out 
special  tools  from  the  tool-room,  and  return  them  as 
soon  as  you  can  conveniently.  Tock  up  your  pri- 
vate tools  only. 

III.  Be  prompt  to  begin  work  and  work  faith- 
fully until  quitting  time. 

IV.  Keep  your  tools  picked  up  and  everything 
clean  and  in  good  order,  so  that  when  you  leave  you 
will  not  be  called  back. 

V.  Be  deliberate  and  thoughtful.  Much  work  is 
spoiled  by  hasty  workmen.  Your  instructor  can  help 
a thoughtful  student. 

VI.  Do  not  tire  your  eyes  by  close  watching  of 
the  fire  or  of  moving  parts  of  machinery.  Use  calipers 
for  close  measurements,  thus  measuring  by  touch 
instead  of  sight.  The  most  skillful  workmen  meas- 
ure to  within  one-thousandth  of  an  inch  by  touch 
with  their  calipers. 


FORCE  AND  MACHINE  WORK. 


7 


VII.  Prepare  to  get  dirty  and  learn  to  use  hot 
water  and  soap  on  your  face  and  hands.  Take  off 
your  good  clothes  and  put  on  overalls.  Relish  and 
make  a business  of  your  work. 

VIII.  Owing  to  the  demand  for  the  use  of  ma- 
chine tools  and  forges,  the  instructor  will  not  hold 
them  for  regular  men  beyond  a reasonabie  time,  say 
fifteen  minutes,  and  will  then  turn  them  over  to 
students  doing  extra  work,  on  application. 

Studcnt^s  Equipment  of  Private  Tools. 

Each  student  makes  a deposit  of  three  dollars 


with  the  Treasurer  of  the  University  for  the  above 
equipment,  which  is  valued  as  follows : 

Key  for  clothes  locker $0.25 

Key  for  tool  drawer 25 

Five  tool- room  checks 25 

Freshman  Tools. 

1 — 9"  scale 35 

1 — 4"  Starrett’s  hair-spring  calipers 65 

1 — 4"  Starrett’s  double-blade  square.  . . 1.25 

Sophomore  and  Junior  Tools.  . 

1 — 6"  spring' tempered  scale 85 

1 — 6"  Starrett’s  hair- spring  calipers...  1.00 
1 graduated  center  gauge 40 


Files  are  provided  when  needed.  Steel  to  make 
lathe  tools  is  given  to  F^reshmen.  These  tools  are 
numbered  and  are  used^  all  through  the  course  in 


8 


MANUAL  OF  INSTRUCTION  IN 


machine  work,  but  are  retained  with  all  private  tools 
at  the  end  of  each  year. 

• The  tool-room  checks  are  given  in  exchange  for 
tools  of  .special  use,  such  as  drills,  reamers,  and  taps. 
The  check  is  forfeited  when  the  tool  is  not  returned 
on  time  or  at  night,  and  when  tools  are  lost  or  broken 
carelessly  the  amount  is  taken  from  the  deposit. 
However,  with  very  few  exceptions,  the  deposit  has 
been  all  refunded. 

The  keys  should  be  placed  on  a ring  with  a brass 
tag  bearing  the  owner’s  name. 

Apply  at  the  office  for  lost  articles. 


FORGE  AFD  MAGHIlS^E  WORK. 


9 


CHAPTER  I. 

Forging  and  Tempering* 

When  the  stndent  enters  upon  this  work,  it  is 
assumed  that  he  has  no  knowledge  of  the  subject 
at  all.  Sometimes  those  who  have  previously  worked 
at  forging  find  it  difficult  to  put  avSide  their  first 
impressions  and  to  take  up  better  methods. 

There  are  several  ways  to  do  every  piece  of 
work,  but  there  is  always  the  best  way.  A student 
who  is  deficient  in  mechanical  ability  can  rarely 
discern  the  best ; one  way  appears  to  him  about  as 
good  as  another ; he  adopts  a certain  order  because 
he  is  told  to  do  so ; when  his  work  is  compared  with 
good  work,  he  sees  no  great  difference ; he  does  not 
see  that  an  eighth  of  an  inch  more  or  less  does  any 
harm,  or  that  80  degrees  or  100  degrees  is  not  as  good 
as  90  degrees.  One  side  of  the  anvil  is  the  same  as 
the  other,  and  he  has  but  little  command  of  motion. 

When  work  is  started  right,  every  serious,  well- 
balanced  student  does  passably  well  in  it.  It  is  a 
mistake  to  insist  upon  excellence  in  everything ; a 
partial  failure  in  a single  direction  should  not  prevent 
his  going  on  in  the  course.  Instead  of  trying  to  force 


10 


MANUAL  OF  INSTRUCTION  IN 


all  into  the  same  mold,  it  is  our  duty  to  give  each  full 
liberty  of  growth,  and  yet  keep  to  our  standard  of 
requirements. 

All  who  attempt  to  make  forgings  should  remem- 
ber that  the  art  of  forging  has  been  recognized 
through  all  ages  as  a trade  worthy  of  the  life-work  of 
many  of  the  world’s  best  men.  And  what  we  do 
with  iron  by  heat  and  hammer  will  be  good  or  bad, 
according  to  our  skill  and  patience.  All  that  is  done 
must  be  with  eyes,  hands,  and  judgment. 

The  operations  of  a forge  shop  involve  a personal 
knowledge  of  four  things : 

1.  How  to  heat  the  piece  to  be  operated  upon. 

2.  How  to  hold  it. 

3.  How  to  strike  it. 

4.  The  kind  of  metal  and  the  effect  of  the  work 
and  heat  upon  the  metal. 

!•  How  to  Heat* 

The  fire  on  a forge  should  receive  constant  atten- 
tion, but  this  does  not  mean  constant  poking  or 
watering;  but  rather  to  the  contrary. 

The  coal  used  in  these  shops  is  the  best  to  be 
had  for  the  purpose,  and  will  do  effective  work.  It  is 
not  entirely  consumed  until  it  becomes  a white  ash 
or  clinker.  The  first  thing  to  do  is  to  separate  the 
partly  burned  coal  or  coke  from  the  ash;  this  is  easy 


FORGE  AFlD  MACHINE  WORK. 


11 


when  the  coke  has  not  been  poked  and  broken  up 
into  small  pieces. 

Start  a fire  with  wood  shavings  and  put  some  of 
the  coke  upon  the  fire,  making  a small  heap  in  the 
center.  Then  pack  damp  coal  around  to  keep  in  the 
blast,  and  use  the  remainder  of  the  coke  to  feed  the 
fire,  for  it  is  comparatively  free  from  gas.  When 
more  coke  is  needed,  the  banks  on  the  side  can  be 
used  if  coked,  and  new  banks  made,  or  fresh  coal  can 
be  put  close  to  the  fire  and  allowed  to  blaze  for  a 
while  until  it  is  partly  coked.  The  whole  secret  of  a 
clean  fire  lies  in  coking  the  fine  coal  into  lumps  the 
size  of  a walnut,  and  allowing  them  to  so  remain  until 
used  up.  To  do  this,  great  care  must  be  exercised  in 
the  use  of  the  blast;  shut  it  off  to  save  a good  fire  and 
be  careful  not  to  use  so  much  blast  as  to  blow  large, 
lumpy,  sparks  out  which  mix  with  the  coal  on  top  of 
the  forge,  which  keep  it  from  coking,  and  give  the 
coal  a lifeless  appearance.  The  forges  are  provided 
with  shakers  to  shake  out  the  fine  ashes  without 
disturbing  the  banks  of  coal.  Team  to  be  econom- 
ical with  coal  for  your  own  good.  A fire  well  banked 
should  last  five  hours  on  light  work. 

In  regulating  the  fire  it  should  not  be  much  hot- 
ter than  the  desired  temperature  (heat);  excessive 
heat  will  overheat  exposed  small  points. 

If  the  fire  is  properly  kept,  a very  small  amount  * 
of  blast  will  do  the  work  except  in  large  welding;  too 
much  air  cools  the  metal. 


12 


MANUAL  OF  INSTRUCTION  IN 


The  fire  should  be  so  arranged  that  the  metal  can 
be  placed  horizontal  and  covered  and  yet  be  easily 
vSeen,  if  the  coke  is  large.  See  that  there  is  plenty  of 
coke  under  the  metal.  If  the  blast  does  not  come 
through,  take  a small  rod  and  stick  it  straight  down 
to  the  tuyere  and  close  to  the  metal;  this  hole  will  be 
all  that  is  needed:  never  should  the  fire  be  poked 
over.  Turn  the  work  over  without  removing  it. 
Give  the  fire  time  to  do  the  heating;  keeping  your 
mind  on  the  next  operation,  so  no  time  is  lost  while 
the  metal  is  hot. 

There  are  three  periods  of  degrees  of  heat  which 
the  writer  wishes  to  make  use  of  to  illustrate  the 
proper  heat  for  metal.  The  first  is  called  a low  heat, 
which  is  before  the  metal  begins  to  scale.  The  sec- 
ond, or  high  heat,  extends  to  the  point  where  the 
scale  melts  and  begins  to  drop  into  the  fire,  if  not 
turned,  and  to  fly  out  into  sparks.  The  third  heat  is 
a welding  heat. 

Each  one  of  these  heats  is  variable  within  the 
limits  mentioned;  but  the  student  must  soon  learn  to 
use  the  heat  desired  within  these  limits.  Too  often 
finished  work  is  heated  to  a high  heat — thus  causing 
a scale  to  be  removed  and  leaving  it  rough  and  (so 
called)  burnt.  So  the  low  heat  is  used  on  metal  that 
is  finished  and  that  should  not  be  scaled.  Metal  is 
bent,  shaped,  and  steel  is  hardened  at  this  heat. 

The  high  heat  is  used  where  metal  is  to  be  forged 


FORGE  A.YD  MACHINE  WORK. 


13 


and  can  afterwards  be  finished  by  the  hammer  when 
it  cools  to  a low  heat. 

The  welding  heat  is  used  to  weld  all  metals,  re- 
fine iron,  for  upsetting,  or  when  a great  amount  of 
forging  is  to  be  done  on  iron  or  soft  steel. 

IL  How  to  Hold* 

The  hand  holding  the  tongs  or  rod  must  be  in- 
timately related  with  the  hammer  and  anvil.  The 
height  will  tend  to  keep  the  work  straight  if  it  is  kept 
turning;  or  if  it  be  held  too  high  or  too  low,  it  will 
crook  the  work  so  it  cannot  be  turned.  In  some 
cases  it  should  be  turned  after  each  hammer  blow; 
this  is  done  partly  by  the  wrist  and  partly  by  rolling 
in  the  hand. 

IIL  How  to  Strike* 

A 2-pound  hammer  is  mostly  used  for  this 
work  with  a 125-pound  anvil;  the  face  of  both  are 
slightly  rounded.  Hold  the  hammer  firmly  while 
directing  blow,  but  the  muscles  of  the  arm  should  be 
relaxed  to  allow  the  hammer  to  rebound.  Avoid  a 
pushing  movement  and  hunching  the  shoulders. 
Keep  nearly  erect,  moving  the  back  and  shoulders  but 
little;  stand  within  easy  reach  of  the  anvil. 

The  end  of  the  hammer  that  has  a straight  or 
cross  pein  is  used  to  spread  metal — a sphere  can 


14 


MAlS^VAL  OF  INSTRUCTION  IN 


be  made  into  a flat  ellipse  or  oval  by  scoring  it  with 
this  cross-pein  to  spread  it  one  way  more  than  the 
other,  while  the  smooth  face  would  tend  to  make  the 
outline  circular.  The  round  edge  of  the  anvil  is  for 
the  same  purpose.  Forgings  should  be  hammered 
hard  enough  to  cause  the  ends  and  sides  to  bulge 
out.  If  the  hammering  is  too  light,  the  outside  only 
will  be  stretched  and  internal  cracks  started,  which 
will  develop  in  bending  or  hardening.  To  accomplish 
this  it  is  best  to  keep  a forging  square  when  pos- 
sible and  change  it  to  a round  or  flat  when  nearly  to 
the  size. 

IV.  The  Kind  of  Metal, 

and  the  effect  on  it  should  be  the  constant  study. 

Iron  during  making  is  melted  in  a puddle  and 
taken  out  in  layers,  and  its  flber  is  lengthwise  like 
that  of  wood.  By  hammering  it  cold,  until  it  cracks, 
the  grain  will  show  to  be  like  wood.  When  a good 
piece  of  iron  is  broken,  it  will  show  a grain  like 
broken  wood.  So  we  can  not  hammer  iron  much  at 
a “low  heat”  until  it  is  refined  by  welding  the  grain 
close  together.  This  is  done  while  forging,  and 
iron  forging  should  not  be  performed  otherwise;  for 
the  fibers  are  sure  to  show  when  the  forging  is 
formed  or  bent  into  shape. 

Norway  iron  is  tougher  than  American  iron  and 
is  very  desirable  where  refining  by  forging  is  impos- 


FORGE  Al^D  MAG  HIRE  WORK. 


15 


sible.  A smith  can  use  poor  iron  and  refine  it  by 
welding  and  make  sound  forgings. 

Mild  Stkkl  is  treated  to  an  air  blast  while  a n?ol- 
ten  mass,  which  renders  it  homogeneous  or  fiberless. 
It  will  not  split  like  iron  or  wood  when  hammered 
cold.  It  is  often  put  in  parts  of  machinery  because 
it  is  tough,  stiff,  and  cheaper  than  the  Norway  iron. 
It  is  not  hardened  with  heat  and  water;  so  the  test  to 
distinguish  it  from  crucible  steel  is  to  try  to  harden 
it.  This  should  always  be  done  at  the  start  to  save 
trouble  later. 

Crucible  Steel  will  harden  readily  by  heat  and 
water.  It  is  melted  while  made  in  an  air-tight  pot. 
Various  grades  and  uses  are  given  this  steel;  the 
lower  grades  are  used  in  machinery  where  special 
hard  stiff  steel  is  needed,  and  the  higher  grades  are 
called  Tool  Steel  and  used  for  fine  cutting  tools.  The 
test  for  the  various  grades  is  their  ability  to  hold  a 
cutting  edge  and  their  performance  in  actual  use.  So 
the  smith  is  careful  to  notice  the  brand  on  every  bar; 
and  must  have  a knowledge  of  the  nature  of  each 
brand.  One  brand  only  of  crucible  steel  is  used  here, 
and  we  call  this  Tool  Steel  to  give  it  a shop  distinction. 

To  summarize,  the  metals  used  are — 

Iron, 

Norway  Iron, 

Machinery  Steel,  and 
Tool  Steel. 


16 


MANUAL  OF  INSTRUCTION  IN 


The  preceding  notes  will  hardly  be  fully  com- 
prehended until  demonstrated  by  practice  and  used 
as  Reference  in  the  work  that  follows. 

The  beginner  should  spend  about  three  hours  in 
preparation  for  the  prescribed  course,  hammering  on 
cold  iron  until  he  is  able  to  turn  it  over  and  pound  on 
all  sides  with  force  and  evenness.  Take  a scrap  of 
round  iron  and  draw  it  out  square  and  turn  it  back 
and  weld  it  into  a flat  bar;  then  twist  it.  Forge  a 
cone  on  the  end  and  spread  it  with  the  cross-pein  into 
an  oval  or  heart-shaped  flat  (see  A,  Fig.  1).  If  the  iron 
splits  or  gets  diamond  shape  or  is  rough  when  com- 
plete, it  is  your  fault—  try  again,  and  study  to  correct 
your  mistakes  and  to  overcome  troubles. 

Twenty  of  the  following  exercises  are  required 
of  each  student  in  forging.  ^ 


No.  1.  (Fig.  1.)  I.  Figure  the  length  of  iron 
required  to  make  it  out  of  a 54  round  bar.  II.  Heat 
to  a welding  heat  on  the  point.  III.  Hammer  the 


FORGE  AFD  MACHINE  WORK, 


17 


point  to  size  first  and  finish  while  still  at  a low  heat. 
IV.  Cut  off*  on  the  hardy  while  warm. 

Use  your  left  hand  skillfully,  to  keep  it  straight. 
The  point  must  be  free  from  splits.  All  must  be  done 
at  one  heat.  Three  trials  will  be  given. 


% 


No.  2.  (Fig.  2.)  Stock  given,  ^"x^"x4"  iron. 

I.  Forge  taper  like  the  sketch  and  square  up  the 
ends  with  the  hammer. 

Noth. — Avoid  splitting,  and  pits  caused  by 
scaling  where  not  hammered ; show  smooth,  straight 
and  symmetrical  hammer-work ; test  with  straight- 
edge; make  cross-lines  show  distinctly.  Use  the  square 
iron  tongs.  Have  a small  fire. 


' 

^ 

■V.J 

■e 'y  ^ 

1 

1 

w 

No.  3.  (Fig.  3.)  Stock  given,  j^"x^"x4"  iron. 
I.  Figure  the  length  of  x. 


18 


MAmAL  OF  INSTRUCTION  IN 


II.  Place  A on  sharp  corner  of  anvil  and  forge 
like  sketch ; hammer  on  the  straight  sides. 

Noth. — Avoid  flaws  at  A,  caused  by  changing 
its  position  on  the  anvil.  Caliper  often.  Scale 
reduces  the  size  of  the  iron. 


No.  4.  (Fig.  4.)  Bent  Ring.  Figure  the  length 
of  3/^"  Rd.  iron  at  the  center  as  indicated  (see  A). 
Stock  given. 

I.  Bend  over  1^"  mandrel. 

Note. — Use  a low  heat.  Do  not  flatten  the  ends. 

No.  5.  (Fig  4.)  Ring  Handle.  Figure  length 
of  Rd.  iron  (x+2")  as  indicated  (see  B).  Stock 
given. 

I.  Dress  ends  and  bend  as  indicated  over  round 
corner  of  the  anvil. 

II.  Bend  on  1"  mandrel. 

Note. — Keep  it  free  from  scars. 


FORGE  AND  MACHINE  WORK. 


19 


No.  6,  (Fig.  5.)  Staple.  Figure  length  of  }(" 
Rd.  iron  to  be  given. 

I.  Draw  Out  square  points  and  bend  over  horn 
and  use  side  of  hardy  to  straighten. 

Note. — Use  welding  heat  on  points,  and  low 
heat  to  bend  center.  Cool  points  in  water.  Must  be 
free  from  marks. 


I.  After  a good  eye  is  made  and  approved,  cut 
the  stock  5"  long  from  center  of  eye. 

II.  Forge  and  bend  hook  to  be  right  after  twist  - 

is  made.  . ‘ 


20  MANUAL  OF  INSTRUCTION  IN 

- - 


III.  Twist  at  low  heat. 

Note;. — Study  carefully  the  heating. 


No.  8.  (Fig.  7.)  Exercise,  Use  extra  length  of 

Norway  iron.  ^ - ;;  ■ 

I.  Draw  on  round  corner  of  anvil  (see  A).  " 

II.  Make  offset  at  D by  upsetting  (see  B).  . " 

III.  Bend  over  horn.  , 

IV.  Cut  and  forge  point.  * 

Noth. — Avoid  nicks  at  D;  make  C sharp. 


/■/>.  8 


No.  9.  (Fig.  8.)  Exercise.  Use  extra  length'  C" 
of  Norway  iron. 

I.  Upset  round  head  plenty  long.  Use  set 
mer  and  heading  tool  to  shoulder  up  at  A. 

II.  Start  the  octagon’at  B with  fullers  ; ham-^’|^ 

mer  to  gauge.  " ' 

III.  Draw  round  part  to  gauge. 


ham-v  y| 


FORGE  AND  MACHINE  WORK,, 


21 


IV.  Cut  and  draw  point. 

Note. — Strike  hard  on  the  end  to  avoid  the  cup 
at  the  end.  Keep  it  central.  Everything  must  be 
hammered.  Take  measurements  from  the  end  to 
avoid  variation. 


• No.  !©•  (Fig.  9.)  UpsetBolts.  Stock,  Rd. 
Norway  iron. 

I.  Upset  bolt  head  by  hammering  on  end  and 
finishing  in  heading  tool. 

II.  Make  one  square  head  and  one  hexagon  head 

bolt. 

Note. — Keep  it  always  central,  avoid  getting  the 
head  too  short,  which  causes  cracks  under  the  head. 
Keep  top  round. 


22 


MAl^UAL  OF  INSTRUCTION  IN 


k — 


No.  11.  (Fig.  10.)  Knee  Forging.  Stock,^^"x^" 
x8"  Norway  iron. 

I.  Upset  in  center  and  bend  as  indicated  (see  A). 

II.  Continue  bending  by  upsetting  (see  B). 
Notk. — Nicks  on  the  inside  will  become  cracks. 

Avoid  drawing  out  sides  on  the  anvil  when  not 
desired.  Use  trysquare  on  outside. 


/7y.  // 

No.  12.  (Fig.  11.)  Chain  Links.  Stock,  3 pcs. 
^"x'7"  Rd.  Norway  iron. 


FORGE  ARD  MACHINE  WORK.  23 


I.  Upset  ends  and  scarf  inside  corners  slightly 
(see  A), 

II.  Weld  in  a clean  fire,  two  links;  put  all  to- 
gether when  welding  the  third. 

Not£^.— Make  weld  at  end  of  links;  leave  it  heavy 
at  weld  and  round. 


No,  13.  (Fig.  12.)  Welded  Bolt.  Stock  for  ring, 
iron;  for  bolt,  4"  of  }4"  Rd.  iron. 

I.  Bend  and  cut  ring  on  hardy  (see  A). 

II.  Upset  bolt  iV"  about  long. 

III.  Put  on  the  ring  and  weld  it  square  as  you  go. 
Put  in  heading  tool  for  squaring  end. 


Note. — Take  the  welding  heat  slow,  to  give  the 
center  time  to  heat.  One  heat  is  enough  for  the  head 
in  (III.);  leave  a fillet  under  head,  if  possible. 


24 


MAl^VAL  OF  INSTRUCTION  IN 


No.  14.  (Fig-  13-)  Stock  of  iron  and  machinery 
steel  varied  in  size  and  shape  by  the  instructor. 

I.  With  the  iron,  upset  and  scarf  the  ends  and 
weld  by  heating  both  ends  at  once  and  laying  to- 
gether on  the  anvil  and  weld  with  the  hammer.  If 
you  are  slow  and  only  get  them  stuck — heat  again 
and  then  weld.  (See  A.) 

II.  With  machinery  steel  upset  and  fork  one 
end  as  in  B and  put  together  tight  before  placing  in 
the  fire  for  a welding  heat. 

Noth. — Much  time  should  be  spent  at  this  exer- 
cise. Have  a clean  fire.  Too  much  blast  and  shallow 
fires  often  .spoil  a welding  heat,  as  it  drives  the  dirt 
onto  the  metal.  Upset  enough  to  have  plenty  in 
welding  and  still  keep  the  metal  full  size.  Strike 
hard  when  welding  the  center. 

Notes  on  Tool  Steel. 

Tool  Steel  is  made  from  the  best  material  and 
should  not  be  carelessly  used.  In  heating,  the  fire 
should  be  well  coked  and  not  hotter  than  needed  to 
bring  the  steel  to  the  desired  heat;  internal  strain  is 
caused  by  fast  heating. 

There  is  no  need  of  scaling  the  steel  to  heat  it 
throughout;  it  is  well  to  take  time,  and  yet  not  best 
to  soak  the  steel  in  the  heat  after  it  is  hot. 

Heavy  pounding,  when  evenly  distributed,  is  a 
benefit  to  hot  steel.  To  do  this,  it  is  best  to  keep  the 
forging  square  at  first  and  change  to  the  desired 


FORGE  A1!^D  machine  WORK, 


25 


shape  when  near  its  completion.  Thin  flats  should 
not  be  hammered  on  edge,  and  often  we  cut  off  the 
edge  rather  than  shatter  the  grain  by  pounding  on  a 
thin  edge.  In  making  small  tools  like  a scratch-awl, 
it  is  possible  to  keep  the  steel  hot  by  hammering. 

Hardening  and  Tempering* 

The  simple  method  of  hardening  steel  in  water 
and  tempering  by  heating  to  the  desired  color  is  the 
only  method  that  we  have  found  necessary  for  any 
tool  that  is  used  in  the  machine  shop.  But  we  use 
only  good  steel  of  a uniform  grade — well  forged. 

If  the  instructor  will  perform  the  following  ex- 
periment before  the  class  it,  will  be  of  great  benefit: — 
Take  a new  bar  of  Tool  Steel,  equal  in  quality  to  the 
Crescent  Extra,  say  3/^"x^"xl2",  and  brighten  one 
side  with  a file  and  file  notches  in  one  corner,  say 
apart,  for  reference.  Now  heat  this  bar  nearly  the 
full  length  so  that  one  end  is  a welding  heat  and  have 
the  heat  gradually  diminish  to  a black,  taking  no- 
tice where  the  red  and  black  seem  to  unite.  Plunge 
this  rod  straight  down  into  soft  water,  and  when 
cool,  take  a fine  file  and  notice  the  following.  First: 
— On  the  side  where  the  original  scale  is  left  you  can 
scratch  it.  This  proves  that  the  scale  is  oxide  of 
iron  and  will  not  harden.  Second: — Test  carefully 

the  hardness  and  you  will  find  it  hard  all  along  the 
part  that  was  heated  up  to  the  point  where  there 
seemed  to  have  been  no  color;  and  that  within 


26 


MANUAL  OF  INSTRUCTION  IN 


of  the  end  of  the  hardened  steel  zV  is  soft.  This  is  a 
valuable  part  of  our  test.  (A)  Steel  will  not  moder- 
ately harden — it  is  either  .hard  or  soft.  (B)  Hardened 
steel  is  a constant  and  a basis  to  work  from  in  tem- 
pering; just  as  we  reckon  the  degrees  of  Centigrade 
from  the  freezing-point.  (C)  It  is  not  necessary  to 
heat  steel  enough  to  scale  it  in  order  to  harden  it. 
Our  best  tools  can  be  finished  before  hardening. 
Third: — Break  the  bar  up  into  small  pieces  and  exam- 
ine the  grain  of  each  piece.  The  over-heated  parts 
will  be  coarse-grained  and  brittle;  but  it  will  improve 
as  the  place  is  approached  where  but  little  heat  was 
given  it  in  hardening.  Also  notice  that  all  the  water- 
cracks  are  found  in  the  part  that  was  very  hot. 

In  conclusion:  The  lowest  heat  that  will  harden 

tool  steel  is  the  best. 

Note. — It  is  necessary  to  harden  annealed  steel 
twice  before  it  becomes  hardened. 

Hardened  steel  is  too  hard  and  brittle  for  most 
purposes;  so  that  it  is  necessary  to  soften  it  a little 
by  heat,  to  suit  the  varied  needs.  This  process  is 
called  tempering. 

The  degree  of  heat  of  polished  iron,  brass,  or  steel 
is  shown  by  its  color  until  it  is  blackened  by  heat. 
For  our  purpose  we  do  not  care  what  degree  Fahren- 
heit is  represented  by  a certain  color;  but  we  do  know 
the  effect  of  the  heat  represented  by  a certain  color 
on  a hardened  piece  of  steel.  So  that  tempering  is 
simply  this:  Harden  the  steel  by  heating  it  to  a low 


FORGE  AND  MACHINE  WORK. 


27 


red  heat  and  plunging  into  water,  leaving  it  in  until 
it  is  cooled;  polish  it  on  one  side  and  heat  it  by  con- 
tact with  a hot  piece  of  metal,  or  hot  sand,  until  the 
color  shows  that  the  steel  has  become  soft  enough 
for  the  desired  purpose.  Then  prevent  its  getting 
softer  by  cooling  it  again.  The  first  color  noticed  is 
yellow  while  the  steel  is  yet  very  hard,  but  as  the  color 
darkens  the  steel  softens;  for  lathe  tools  a straw 
color  is  needed — cold-chisels  a blue,  screwdrivers  a 
blue-black.  A color-tempering  scale  for  various 
tools  in  use  can  be  seen  on  the  shop  wall.  This 
scale  is  taken  from  Vol.  II.  of  Appleton’s  Cyclopedia 
of  Applied  Mechanics. 

In  tempering  the  cold-chisel  or  lathe  tool,  it  is 
best  to  heat  the  body  part  a black  warm,  and  the 
point  to  be  hardened  a low  red  heat. 

Harden  the  part  to  be  tempered  in  water  and 
when  removed  the  wet  should  not  dry  off  in  steam, 
for  that  indicates  that  the  cooled  part  is  being  heated 
very  fast,  from  the  body  part  v/hich  is  still  warm. 
While  it  is  slowly  heating,  polish  the  point  and  watch 
for  the  desired  color  which  indicates  a softening  of 
the  steel.  Redip  the  tempered  part  when  desired  to 
keep  the  temper,  but  do  not  dip  the  body  until  it  has 
cooled  beyond  the  point  where  it  will  harden.  Skill 
is  required  to  have  the  color  run  slowly,  by  getting 
the  right  amount  of  heat  in  the  body  to  produce  the 
color.  The  slower  the  color  runs  the  more  even  will 
be  the  temper. 


28 


MANUAL  OF  INSTRUCTION  IN 


When  steel  is  to  be  tempered  evenly  all  over,  it 
is  first  hardened  all  over,  polished,  then  put  in  con- 
tact with  hot  sand  or  iron  until  the  desired  color  is 
reached. 

Note. — Remember  that  the  color  of  polished 
steel  does  not  indicate  its  temper ; it  only  shows  a heat, 
and  unless  the  whole  process  of  tempering  is  known, 
the  color  is  of  no  value;  the  first  color  after  harden- 
ing is  the  only  one  of  value  by  observation. 

The  above  will  be  a foundation  for  extended 
study ; and  special  work  should  be  referred  to  the 
instructor,  whose  experience  and  judgment  are  needed 
in  deciding  special  methods ; all  of  which,  however, 
involve  the  above  principles. 

Annealing* 

Annealing  steel  is  to  soften  it  for  easy  cutting. 
After  heating  to  a low  heat,  put  it  in  a lime-box,  or 
similar  air-tight  place,  to  keep  it  warm  for  some  time, 
and  it  will  become  quite  soft,  so  that  threads  can  be 
cut  on  it. 

Water  Annealing  is  a method  of  softening  steel 
by  heat  and  water.  When  the  steel  is  at  a point  of 
heat  that  is  hardly  seen  in  a dark  place,  it  is  softened 
by  water,  much  softer  than  if  it  were  allowed  to  cool 
naturally.  This  process  is  used  when  holes  are  to  be 
drilled  in  the  end  of  tool  steel  forgings  or  returning 
lathe  centers. 

Case  Hardening  is  produced  by  the  application  of 


FORGE  MACHINE  V^  ORK, 


29 


cyanide  or  yellow  prussiate  of  potash  on  iron  or  ma- 
chinery steel  while  it  is  red-hot  and  immediately 
plunged  into  water,  which  gives  it  a hard  coat.  This 
method  is  used  on  nuts  and  screws  for  machines  and 
bicycles.  The  success  of  the  operation  is  indicated 
by  the  snap  as  it  is  plunged  into  the  water  hot.  Tool 
steel  is  never  treated  in  this  way. 


F/yJV. 


‘t 


No.  15.  (Fig.  14.)  Scratch'Awl.  Stock,  3"  of 

Oct.  Tool  Steel. 

I.  Draw  it  out  to  square  and  5^"  long. 

II.  Twist  it  360  degrees  as  indicated. 

III.  Draw  each  end  to  a round  point  yV'  diam- 
eter. Grind  the  point  before  bending  down 

IV.  Temper  to  a straw  color  on  each  end. 

Note. — Grinding,  except  on  points,  is  not  al- 
lowed ; make  corners  of  twist  sharp  with  the  ham- 
mer. Show  skillful  hammering. 


No.  16.  (Fig.  15.)  Center  Punch.  Stock,  3 
Oct.  Tool  Steel. 


30 


MAIS^VAL  OF  INSTRUQTION  IN 


I.  Draw  to  a square  point  at  a low  heat  and  then 
change  to  round. 

II.  Grind  point  60  degrees  and  temper  it  dark 
straw  color. 

Notk. — Show  hammering,  and  not  grinding. 


No.  17.  (Fig.  16.)  Cold^Chisel.  Stock,  6"  of 
Oct.  Tool  Steel. 

I.  Hammer  by  hand  at  low  heat,  keeping  it 
square  for  awhile,  then  flatten.  If  it  is  a little  too 
wide  when  nearly  finished,  grind  it  oflf,  rather  than 
strike  the  thin  edge  and  shatter  the  grain. 

II.  Grind  the  edge  60  degrees. 

III.  Temper  blue  and  test. 

Note. — No  finish  by  grinding  allowed. 


No.  18.  (Fig.  17.)  Diamond-point  lathe  tool. 
Stock,  ^"xl"  Tpol  Steel  given. 

I.  Forge  on  corner  of  anvil  as  indicated  and  cut 


FORGE  AND  MACHINE  WORK. 


31 


off  point  so  that  A will  be  above  top  and  higher 
than  B. 

II.  Grind  top  and  front  of  tool. 

III.  Temper  a straw  color. 

Note. — Test  your  stock  for  Tool  Steel,  if  neces- 
sary. Use  hammer  only  in  forging. 


No.^  19.  (Fig.  18.)  Cutting^off  Tool.  Stock 
given. 

I.  Forge  with  hammer,  keeping  AB  well  slanted 
until  nearly  finished,  then  do  not  strike  the  edge. 

II.  Cut  oflF  at  BC. 

III.  Grind  carefully  to  leave  the  point  wider 
than  any*  other  part,  and  sides  flaring,  so  that  it  will 
follow  its  own  cut,  made  by  cuttin'g  edge  C. 

IV.  Harden  the  top  only  and  temper  dark  straw. 
Note. — If  the  sides  are  finished  carefully  with  a 

hammer,  they  will  need  no  grinding.  If  desired,  a 
slant  DE  may  be  given. 


No.  20.  (Fig.  19.)  Side-cutting  Tool.  Stock 
given. 

I.  Forge  this  tool  the  same  as  No.  19,  except  the 
cutting  edge  is  on  one  side  EF,  so  it  is  left  full  width 
at  the  bottom  and  flares  at  CD.  Slope  AB  with  ham- 
mer and  cut  off  at  CB. 

II.  Grind  on  top  and  side  surface  CD. 

III.  Temper  top  to  straw. 


No.  21.  (Fig.  20.)  Pliers,  Stock,  2 pcs.  >^"xl" 
x4"  Mch.  Steel. 


FORGE  AND  MACHINE  WORK. 


33 


T.  Test  stock  and  hammer  over  corner  of  anvil  to 
general  form  (see  the  sketch  above  the  drawing). 

II.  Finish  jaw  and  round  part,  then  the  handles. 
Note. — Smooth,  accurate  forgings  are  necessary; 
leave  handles  smooth-hammered  ; notice  their  cross- 
section  and  position  from  the  center  line. 

Every  student  is  required  to  complete  these  pliers. 


The  test  of  ability  is  given  in  work  that  follows 
where  no  instructions  are  laid  out,  and  one's  judg- 
ment is  all  that  is  reliable.  Students  of  different 
courses  of  engineering  could  now  do  special  work  in 
their  own  lines,  under  the  help  of  the  instrhctor. 


Figs.  21«to^25  are'^only  a few  of  the  exercises- 
suggested;  others  hiay  be  seen  on  the  sample-board  in 
the  shop. 


f/y.  21. 


FORGE  AND  MACHINE  WORK. 


35 


I 

ri 


G/i /^ead /^ey 


I 


/=7y.  2 


ir 


CHAPTER  II. 

Bench  Worfc* 

Bench  work  consist  in  the  use  of  hand  tools  and 
mainly  consists  in  filing,  chipping,  and  drilling  small 
holes  with  the  drill  press. 

No  heat  is  used  as  in  forging  and  the  metal  is  re- 
duced by  cutting  to  suit  the  purpose  for  which  it  is 
made.  And  yet  the  cutting  done  by  the  file  and 
chisel  at  the  bench  can  not  well  be  done  by  the 
machine  tools.  Each  has  its  work  and  usefulness. 

Filing,  though  not  hard  work,  requires  patience 
and  attention  to  style  of  motion.  In  one  respect,  like 
forging,  it  is  dependent  upon  the  eyes,  hands,  and 
judgement;  practice  in  movement  is  required  similar 
to  that  in  beginning  penmanship.  Both  hands  are 
always  used  in  filing;  the  right  hand  is  held  close 
to  the  side  with  the  wrist  curved  so  the  file  can 
be  moved  nearly  straight  out  from  the  body;  the 


36 


MAl^VAL  OF  INSTRUCTION  IN 


thumb  resting  on  top  of  the  handle  and  the  end  of 
the  handle  resting  against  the  palm  of  the  hand;  the 
left  hand  resting  on  top  of  the  file,  at  the  end,  with 
the  fingers  gently  grasping  the  file  so  that  the  fore- 
arm is  at  an  angle  of  about  45  degrees  with  the  file. 
The  vise  should  be  within  easy  reach  and  of  a height 
to  permit  the  forearm  to  be  level  and  the  body  erect. 

No  great  pressure  is  needed  on  the  file  in  the 
cutting  stroke,  for  the  object  of  good  filing  is  to  pro- 
duce sraight  work,  and  not  to  remove  metal.  Do  not 
raise  the  file  oflf  entire  y on  the  return  stroke,  but  do 
not  drag  it  back  hard.  The  similarity  in  movement 
is  easier  to  maintain  than  a repeated  routine  of  sever- 
al movements.  When  the  file  is  cutting,  the  student 
should  observe  its  effect  without  stopping  the  file. 
Adjust  the  hand  to  suit,  until  the  desired  results  are 
obtained.  It  is  necessary  to  change  the  position  to 
make  the  lines  of  the  filing  show  plainly  and  cross- 
cut each  other  to  prevent  filing  uneven. 

Do  not  file  when  you  have  no  knowledge  of  the 
effect.  7 

The  student  should  first  take  a short  stroke,  and 
gradually  learn  the  longer  stroke  in  two  or  three 
days.  Use  the  rough  file  to  get  the  work  straight, 
only  using  the  mill  file  to  smooth  it  up  just  at  the 
last.  It  is  sometimes  best  to  draw  file  with  the  mill 
♦ file  to  keep  it  from  clogging  up  and  scratching. 

To  do  this,  put  the  file  cross-wise[and  file  both 
ways  with  a short,  quick,  movement.  Drawfiling  is 


FORGE  ARD  MACHINE  WORK. 


37 


not  practical  and  should  only  be  done  to  smoothen 
iron.  Some  kinds  of  work  need  not  be  drawfiled,  as 
the  double-cut,  rough  file  will  leave  it  sufficiently 
smooth.  A straight  surface  is  more  necessary  than 
a smooth  surface  and  the  former  should  not  be  sacri- 
ficed for  the  latter.  Test  the  surface  with  straight- 
edge and  surfape  plate,  or  when  parallel  surfaces  are 
made,  test  with  the  calipers  by  so  adjusting  them 
that  they  are  loose  in  one  place  and  tight  in  another, 
for  comparison.  Do  not  depend  upon  the  friction  of 
calipers  to  ascertain  variations  in  the  thickness.  Take 
off  the  wire  edge  with  the  file  before  testing. 


‘S 

A 

1 

^ 

No.  1.  (Fig.  26.  Exercise.  Stock  ^"x^"x3" 
of  iron  and  a square  nut.  Kept  in  tool-room. 

I.  Practice  filing  on  the  ends  of  A,  using  the 
edge  of  the  file  to  take  off*  the  roughness.  Do  no 
drawfiling. 

II.  File  two  adjoining  sides  of  A true  and  90 
degrees,  leaving  two  sides  black.  Have  your  work 
inspected  by  the  instructor. 

III.  Finish  the  ends  93  degrees  regardless  of 
length. 


38  MAmAL  OF  INSTRUCTION  IN 


IV.  File  the  square  surface  of  B true  to  the  sur- 
face plate.  Grind  off  any  thick  scale  that  might  be 
on  the  nut;  it  ruins  the  file. 

V.  File  two  opposite  sides  parallel  and  90  de- 
grees from  the  face,  making  the  hole  central;  using 
the  calipers  at  this  place  will  be  quite  a study  and 
should  be  given  close  attention.  The  hair-spring 
screw  should  be  adjusted  very  freely  to  assist  in  their 
proper  use. 

VI.  File  remaining  two  sides  the  same;  making 
both  diameters  equal,  all  angles  90  degrees. 

Noth.- — By  filing  opposite  sides  in  this  way,  no 
great  error  in  the  angles  can  be  made,  the  work  will 
check  itself,  an  imperfect  square  can  be  detected  and 
used  as  well  as  a true  square. 

VII.  Mark  out  a square  hole  on  both  sides, 
with  your  scratch-awl,  making  the  hole  central. 

VIII.  Check  out  a rough  square  file  and  a par- 
allel three-cornered  file,  using  the  latter  to  finish 
filing  the  hole.  Keep  the  walls  of  the  nut  parallel 
and  equal;  leave  the  corners  a little  round  like  those 
of  the  file.  Use  the  calipers  to  get  the  walls  equal 
and  thus  produce  a square  hole.  Inspection. 

IX.  File  the  black  sides  of  A to  fit  in  B,  and 
when  driving  it  in  lightly,  you  may  be  able  to  im- 
prove the  hole.  A should  fit  into  B in  any  way.  File 
off  the  corners  of  A so  they  will  not  quite  touch. 

X.  Polish  all  exterior  parts  except  the  fitting 
and  black  parts.  Put  the  emery-cloth  under  the  file 


FORGE  Al^D  MAG  HIRE  WORK. 


39 


and  use  the  coarse  freely  to  remove  the  file-marks 
and  polish  with  the  fine  cloth.  Avoid  rounding  the 
corners. 

Nqtk. — You  will  notice  the  black  grain  of  the 
iron;  do  not  try  to  work  it  out. 

In  this  exercise  the  student  should  learn  to  file 
just  where  desired  and  true.  All  who  complete  No. 
1 well  and  file  well,  having  a good  movement,  need 
not  do  No.  3. 

Call  on  instructor  to  inspect  each  of  the  ten  oper- 
ations if  desired.  Always  start  right  and  keep  right. 

The  drill  press  is  very  easy  to  manage  in  the 
work  that  follows.  The  work  is  clamped  in  the  vise 
or  clamp.  Do  not  try  to  hold  work  by  hand  until 
your  experience  will  insure  success.  The  drills  and 
the  countersinks  are  checked  out  of  the  tool- room. 
75-degree  countersinks  for  screws  and  rivets  have 
an  octagon  shank.  Grind  your  own  drills  on  the 
face  of  the  grindstone,  holding  the  cutting  edge  up 
and  parallel  with  the  axis  of  the  stone  and  keep  it 
parallel  while  rounding  the  heel  off  for  clearance. 
Make  the  lips  the  same  length  by  measurement;  but 
no  special  gauge  is  needed  for  the  drills  used  in  the 
work  here  given. 

Lard  oil  is  found  in  the  large  cans  and  is  used 
in  drilling  wrought  iron  or  steel,  but  very  little  is. 
needed;  about  three  drops  placed  on  the  drill  about 
one  inch  above  the  work  while  the  drill  is  cutting 


40 


MAl^^UAL  OF  INSTRUCTION  IN 


will  be  all  that  is  needed  in  drilling  holes  in  }("' 
plates. 

Use  the  fastest  or  first  speed  for  holes  up  to 
the  second  for  holes  to  the  third  from 
to  the  fourth  from  ff"  to  for  all  metals  ex- 
cept tool  steel. 

Be  careful  in  using  the  self-feed,  it  is  quite  fast 
for  small  drills.  The  drill  should  be  fed  enough  to 
cause  the  chips  to  curl.  Do  not  allow  the  drill  to 
slip  and  harden  the  surface  to  be  cut.  Have  waste 
handy  and  keep  work  clean. 


No.  2,  (Fig.  27.)  Varified  Exercise. 

I.  Cut  oflF  the  stock  ^"xl^"x3"  from  a bar  of 

iron.  / 

II.  File  ends  long  for  convenience  in 

measuring. 


FORGE  AND  MACHINE  WORK. 


41 


III.  Mark  the  rectangle  and  holes  to  be  drilled 
by  pricking  the  centers  with  center-punch,  then 
scribe  the  circles  with  dividers  kept  in  the  tool-room. 
Put  four  prick  punch-marks  on  each  circle  to  locate 
them  permanently. 

IV.  Hold  the  work  in  the  drill  clamp  and  start 
the  drill  cutting,  but  before  it  cuts  full  size,  compare 
the  outline  of  the  drill  with  the  circle  on  the  work. 
If  it  is  not  true,  it  must  be  moved  by  punching  a hole 
in  the  countersink  with  the  center-punch,  which  will 
cause  the  drill  to  cut  more  on  that  side.  The  drill 
does  not  always  follow  its  point  and  must  be  thus 
changed.  After  drilling  and  countersinking  the 
holes, 

V.  Cut  out  the  rectangle;  hold  in  vise  and  cut 
center  with  your  chisel  so  you  can  get  the  file  started. 
Chip  towards  the  metal. 

VI.  File  inside  to  measurement.  Do  no  pol- 
ishing. 


No.  3,  (Fig.  28.)  Quiz.  Time  given  is  three 
to  four  hours.  Stock,  section  of  steel  shaft  1 
long,  from  tool-room. 


42 


MA^AL  OF  INSTRUCTION  IN 


I.  File  a true  hexagon;  file  sides  AB  perfect, 
then  CD  parallel  to  AB,  and  EF  last,  using  calipers  to 
check  errors.  Use  the  special  blade  of  the  square. 
Make  perfect  as  you  go.  Polish. 


No.  4,  (Fig.  29.)  Exercise  in  Close  Drilling, 

I.  Cut  the  stock  off  of  bar  of  iron. 

II.  File  ends. 

III.  Lay  off  and  scribe  holes  in  one  plate  as  in 
No.  2. 

IV.  Start  all  the  holes  with  the  drill.  Then 
clamp  both  together  in  drill  vise  and  drill  through  all 
the  holes;  countersink  one  plate  as  indicated.  Clean 
well  and  have  them  inspected. 

V.  Rivet  the  plates  together  reversed.  Make 
the  rivets  of  Norway  Iron  }("  longer  than  the 
holes.  Use  the  round  pein  of  the  hammer  to  fill  up 
the  countersink  and  both  hammer  and  rivet-set  on 
the  rounded  ends.  Pound  enough  to  head  it  well, 
but  not  to  split  the  plates. 


FORGE  Al^D  MACHi:S[E  WORK, 


43 


Noth. — Let  the  riveting  be  purely  hammering 
and  do  not  file  or  chip  the  heads. 


No.  5.  (Fig.  30.)  Key  Filing*  Stock  >^"x^"x3" 
Mich.  Steel  from  bar  or  Fig.  25.  Keys  are  parallel 
and  close  fitting  on  the  sides;  they  taper  about 
to  the  foot  on  top  or  side  which  touches  the  hub  only. 
The  widths  are  made  to  suit  a stock  size  bar  of  steel 
nearest  in  size  to  one  quarter  the  diameter  of  the 
shaft.  But  little  or  no  filing  is  needed  on  the  sides, 
the  bottom  is  made  straight  and  the  top  may  be  made 
rounding  or  any  shape  to  fit  the  taper  of  the  hub 
when  in  its  place  very  tight. 

I.  File  key  to  size  by  measurement  so  that  it 
will  partly  enter  into  its  place. 

II.  Drive  it  in  lightly,  well  oiled.  File  bright 
spots,  and  repeat  until  the  bright  part  extends  full 
length  and  width;  leaving  projecting  to  be  driven 
in  tight  at  a future  time. 

III.  File  ends  like  the  sketch.  Polish  ends  only. 

Note.—No  draw-filing  is  needed  on  this  key 

until  at  the  last  touch;  file  lengthwise  with  rough 
file.  This  work  requires  about  two  hours.  Find  hub 
and  key  drift  in  tool-room. 


44 


MAIS^VAL  OF  INSTRUCTION  IN 


No.  6.  Surface  Plate. — Stock  given  from  spe- 
cial soft  cast  iron.  ^ 

This  exercise  introduces  chipping  with  the  stu- 
dent’s own  chisel  and  scraping  to  a true  surface. 

I.  In  chipping  have  your  chisel  about  thick; 
ground  60  degrees.  Do  not  take  off  more  than  }i" 
cut  at  a time.  Use  a 1^ -pound  hammer,  gripping 
the  handle  about  9"  from  the  head;  swing  it  over  the 
shoulder  steadily  and  evenly,  using  a movement  from 
arm  and  wrist.  Soft  “feeling”  taps  are  not  allowed. 
Hold  the  chisel  loosely  and  cut  toward  the  center  to 
avoid  breaking  off  the  edges  of  the  iron.  Take  oflF 
two  cuts. 

II.  Chip  the  edges  to  complete  a square. 

III.  File  with  the  rough  file  t6  surface  plate. 
The  edge  of  the  file  can  be  used  to  advantage. 

IV.  In  scraping,  grind  the  scraper  as  straight  as 
possible  on  the  side  of  a smooth  wheel;  whet  it  on  an 
oilstone  until  very  true.  Scrape  quite  heavy  at  first, 
to  keep  the  metal  rough  until  nearly  level.  Then 
shorten  up  the  stroke  with  care  to  finish  well,  chang- 
ing the  position  often  to  prevent  making  vibrations 
and  grooves.  When  finished,  it  should  touch  about 
half  its  surface  on  a dry  test  surface  plate ; all  the 
corners  and  edges  must  touch. 

Be  careful  to  have  no  dust  between  the  plates, 
and  put  one  drop  of  oil  on  and  rub  the  test-plate  with 
the  hand  to  get  the  oil  off  and  insure  a clean  surface. 


FORGE  AiYi)  MACHINE  WORK. 


45 


V.  Scrape  the  edges  true;  frost  them  by  making 
irregular  spots  at  regular  intervals. 

Notk.^ — In  cutting  your  plate  out  of  a large  plate 
of  cast-iron,  drill  a series  of  holes  around  it,  that  will 
cause  it  to  break  out  easily. 

Scraping  is  the  finish  given  to  all  planed  work  of 
machine  tools  and  engines  where  true  surfaces  are 
needed.  Scraped  surfaces  wear  well.  Take  pride  in 
your  chisel. 

Insert  a brass  name-plate  in  the  edge,  if  you 
desire. 

Wearing  a glove  on  the  left  hand  while  chipping 
is  considered  wise  and  good  taste. 

Chipping  an  offset  on  the  edges  held  by  the  vise 
will  prevent  the  plate  slipping  down.  Cut  cross  wise 
the  vise.  Use  the  heavier  vise. 


No.  7.  (Fig.  31.)  Inside  Calipers.  Stock,  Tool 


Steel. 

I.  Cut  stock  out  on  the  shears ; cut  close  to  the 
line  and  do  not  have  unnecessary  filing. 


/ 

46  MA1\  VAL  OF  INSTRUCTION  IN 


II.  Drill  }("  hole  and  file  edges  like  sketch  A. 

III.  Bend  points  in  forge  shop. 

IV.  File  and  polish  sides  like  sketch  B;  free 
from  scratches.  See  that  the  joint  around  the  hole  is 
parallel  and  well  surfaced. 

V.  Put  together  with  washers  kept  by  the  in- 
structor. See  that  the  machinery  steel  pin  fills  the 
hole  in  the  legs  tight.  Leave  on  each  end  for 
riveting.  The  washers  are  made  concave  to  spring 
and  take  up  the  wear.  Oil  the  joints.  File  off*  the 
rivet  smooth  and  rounding,  polish  by  hand  and  then 
polish  to  a circular  polish  by  use  of  the  drill-press 
and  a small  piece  of  emery-cloth  stretched  over  a 
stick  held  in  the  clamp. 

VI.  File  the  sides  of  the  legs  tangent  to  the  end 
curves,  when  legs  are  at  90  degrees. 

VII.  Stamp  your  name  on  the  inside,  if  desired. 

Noth. — Use  calipers  in  IV. 


FORGE  MACHINE  WORK. 


47 


No.  8.  (Fig.  32.)  Side^cutting  Pliers.  Stock, 
Fig.  20. 

The  student  is  expected  to  show  taste  in  making 
these  pliers,  in  things  that  can  not  be  shown  well 
here.  Bvery  student  is  required  to  finish  them  as  in- 
dicated below. 

I.  Mark  the  center  line  and  circles  for  boring 
and  locate  permanent  marks  with  the  pick-punch. 

II.  Drill  hole  by  resting  the  forging  on  a 
level  strip  of  iron  in  the  clamp.  See  that  the  pliers  are 
smooth  on  the  bottom  side. 

III.  Forge  a pin-drill  from  stock  kept  in  the 
tool-room,  finish  to  size  by  filing,  and  temper  dark 
straw.  Make  it  as  large  as  possible  to  suit  the  pliers. 

IV.  Countersink  each  piece  to  exact  depth, 
using  a parallel  block  to  bore  on.  Return  drill  as 
soon  as  possible,  so  others  can  make  one. 

V.  File  carefully  to  fit  them  together;  file  jaw 
to  the  center  line.  Teave  shoulders  as  indicated  to 
open  to. 

VI.  Make  cutters  as  indicated,  of  tool  steel  stock 
kept  in  the  tool-room.  Fit  them  to  each  jaw,  making 
the  dovetail  part  to  suit  a three-cornered  file.  Allow 
some  for  shrinking  in  tempering.  File  cutting 
edges  60  degrees  and  in  line  with  the  corner  of  the 
jaw,  as  indicated;  score  the  jaws  with  a file.  Run  a 

drill  through  the  hole  while  the  pliers  are  together, 
so  the  pin  will  not  bind. 


48 


MA^AL  OF  INSTRUCTION  IN 


VII.  Gase-harden  the  jaws  and  temper  the 
cutters  to  a straw-color. 

VIII.  Oil  well  and  rivet  together,  striking  the 
rivet  lightly  to  head  it  without  swelling  th^  body. 
When  finished,  loosen  the  rivet  over  a hole. 

Note. — A well-forged  pair  of  pliers  needs  no 
bright  finish  on  the  handles.  Polish  around  the  jaws. 
Stamp  your  name  on  the  inside  of  the  handles,  which 
will  prove  the  maker.  Test  the  cutters  with  an  8-d. 
wire  nail. 

T" 
tc* 

/i 

A. 

r/j.3S. 

No.  9.  (Fig.  33.)  Ratchet  drilling.  The  ratchet- 
drill  is  a tool  used  to  drill  holes  by  hand  where  the 
power-drill  cannot  be  used.  The  '‘old  man”  is  the 
frame-work  that  is  put  up  to  hold  the  “ratchet”  and 
drill. 

I.  Forge  a drill  out  of  stock  kept  in  tool-room. 
Temper  to  dark  straw-color.  Finish  by  grinding  on 
the  stone. 

II.  The  iron  given  by  the  instructor  to  be  drilled 
can  be  clamped  in  the  vise  and  the  “old  man”  clamped 
on  to  it. 

III.  Use  no  oil  on  the  drill  when  drilling  cast 
iron.  Place  your  thumb  so  the  edge  of  the  drill 
touches  it  as  they  pass  when  turning;  if  one  side 


FORGE  AND  MACHINE  WORK. 


49 


swings  out  more  than  the  other,  your  drill  point  is 
not  central  and  will  cut  too  large.  Grind  true.  The 
rounded  edges  at  A will  be  a benefit  in  this  respect. 

NoTiE. — This  exercise  can  be  done  in  two  hours. 
Students  who  have  previously  done  this  work,  and 
who  can  pass  an  oral  examination  upon  the  subjects, 
are  excused  from  Nos.  9,  10,  and  11. 

No.  10.  Pipe^cutting.  This  work  is  intended 
merely  to  show  the  method  of  cutting  small  pipe  by 
hand. 

The  nominal  measurement  of  pipe  is  taken  on 
the  inside.  The  thread  is  cut  taper  of  to  1 ft , 
and  should  be  tight  on  the  end  of  the  pipe  and  never 
allowed  to  go  in  to  the  shoulder  of  the  thread.  Cut  the 
thread  to  fit  the  fittings  (ells  and  tees)  and  adjust  the 
die  to  suit.  The  marks  on  the  die  for  standard  size 
may  not  be  correct.  Cut  all  at  one  cut,  using  lard  oil; 
the  pipe  should  just  come  through  the  die.  Be  sure 
the  guide  fits  well. 

- , I.  Cut  one  thread  on  a 1"  pipe. 

II.  Cut  it  off  three  inches  long  for  a nipple. 

III.  Cut  threads  on  the  other  end  by  holding  the 
nipple  in  a holder.  File  off  the  burrs  and  give  it  a 
neat  appearance.  This  is  a short  exercise. 

No.  11.  Babbitting.  Provisions  are  made  to 
babbitt  two  boxes  which  are  made  in  halves. 

I.  Cut  out  the  babbitt,  running  a narrow  (cape) 
chisel  lengthwise  through  the  babbitt  at  the  bottom. 
Clean  out  the  retaining-holes. 


50 


MA^^UAL  OF  INSTRUCTION  IN 


II.  Support  the  shaft  on  blocks  so  that  it  is 
central  with  the  parting. 

III.  Putty  up  around  the  ends;  cement  the  putty 
to  the  box  and  shaft  with  fingers,  but  be  careful  not 
to  crowd  it  in  under.  Put  card-board  covers  on  the 
parting,  leaving  large  vents  and  pouring  holes. 

IV.  Add  a little  babbitt  to  what  was  taken  out 
and  melt  slowly  in  a ladle  until  a soft  stick  will 
smoke  when  touched  to  it.  Pour  into  the  box  as 
fast  as  it  will  take  it;  keep  the  face  at  a safe  distance. 

V.  Take  out  the  shaft  and  scrape  the  sides  of 
the  babbitt  so  the  shaft  will  lie  on  the  bottom  and 
turn  easily.  Boxes  should  never  touch  hard  on  the 
sides. 

VI.  Put  the  shaft  back  and  put  the  cap  in  place 
with  liners  of  card-board  between,  to  be  removed  or 
reduced  when  necessary  to  take  the  up  wear.  Putty 
up  the  ends,  leave  vents,  and  put  a high  pouring- 
spout  of  putty  on  top.  Pour  as  before. 

VII.  Scrape  the  cap,  drill  oil-holes  and  cut  oil- 
grooves. 

VIII.  Increase  or  reduce  the  liners  so  that  the 
cap  can  be  tightened  and  still  have  the  shaft  a 
neat  fit. 

The  cap  and  box  are  sometimes  poured  at  the 
same  time  with  liners  between,  cut  to  allow  the 
metal  to  pass  and  still  easily  break  and  allow  them 
to  separate. 

Note  — Consult  the  forge  instructor  about  melt- 


FORGE  AND  MACHINE  MORE, 


51 


ing  the  babbitt.  Only  certain  forges  are  used  for 
this  purpose. 

It  is  often  necessary  to  warm  the  shaft  to  keep 
the  metal  from  chilling  in  rough  waves.  Some- 
times a thin  layer  of  paper  on  the  shaft  will  insulate 
it  and  cause  the  metal  to  run  smooth.  Oil  is  used 
for  this  purpose.  In  babbitting  solid  boxes,  white 
lead  put  on  the  shaft  as  a paint  will  insure  good 
work  and  give  room  for  removing  the  shaft,  which  is 
done  at  once.. 

This  completes  the  work  given  on  this  subject 
at  this  time. 

The  study  of  construction  of  machinery  by  hand 
in  a technical  way  is  given  in  the  class-room  later. 
But  the  student  is  asked  to  study  the  Appendix  with 
a view  to  using  correct  names  for  some  of  the  com- 
mon articles  in  the  shop. 

Students  who  have  time  and  who  stand  well  in 
their  classes  are  given  use  of  the  wood  tools  and 
may  make  things  of  their  own  design,  if  the  design 
is  approved  by  the  instructor. 


CHAPTER  III. 

Machine  Tool  Work* 

The  work  of  machine  tools  consists  in  cutting 
the  metal  by  tools  which  give  it  geometrical  forms 
and  shapes. 

The  machine  tool  is  an  instrument  of  great  pre- 


52 


MAl^UAL  OF  IFfBTRVCTIOFl  IN 


cision,  yet  good  work  will  not  be  performed  unless  it 
is  intelligently  operated. 

The  writer  does  not  wish  to  exhaust  the  capacity 
of  machine  tools  or  any  one  of  them,  nor  to  take  up 
in  detail  each  feature  of  every  tool;  but  rather  to 
show  the  operations  of  lathe-work,  which  will  be 
uniformly  taught  and  similar,  until  sufficient  knowl- 
edge is  obtained  to  enable  the  student  to  branch  out 
to  other  tools  and  perform  special  work  which  will 
be  put  to  some  good  use,  either  by  itself  or  collect- 
ively in  the  machinery  which  is  built  by  the  students. 

The  lathe  is  constructed  and  operated  on  very 
simple  principles  and  becomes  more  and  more  com- 
plex in  its  results  the  more  it  is  used  and  studied. 
It  is  capable  of  doing  the  most  of  the  work  in  build- 
ing machinery  and  the  student  is  expected  to  devote 
the  most  of  his  time  to  the  study  of  the  lathe;  not  only 
to  manipulate  the  various  movements  with  judg- 
ment, but  rather  to  produce  true  work  under  all  con- 
ditions, and  make  good  fits. 

. The  student  is  given  a 14"x6  ft.  engine  lathe  to 
study  and  look  over  with  a view  to  answering  the 
following  questions  to  the  instructor:  What  is  the 

live  spindle?  Tail-stock  spindle?  How  are  the  cen- 
ters extracted?  When  is  each  center  considered  true? 
What  is  the  chuck;  faceplate  (how  removed);  back- 
gear;  single  gear;  lead-screw  and  half-nut;  straight- 
and  cross  feed;  compound-rest? 

The  following  general  terms  are  used:  '‘Rough- 


FORGE  AFD  MACHINE  WORK. 


53 


ing-cut,”  is  to  cut  the  metal  to  nearly  its  desired  size 
or  a cut  for  removing  metal  only.  ‘‘Finishing-cut,” 
for  finishing.  “Facing,”  is  cutting  cross-wnse.  True- 
ing-up,”  is  to  place  the  work  in  the  lathe  true  with 
the  parts  which  can  be  turned  but  little,  or  not  at  all. 
“Centering,”  is  to  put  the  cone  bearings  in  the  work 
for  the  centers.  “Drilling,”  is  done  with  a drill; 
“boring,”  with  a tool;  “reaming,”  with  a reamer; 
“threading,”  or  to  cut  thread,  should  always  be  done 
with  a single-pointed  tool. 

The  modern  method  of  standardization  is  used 
more  in  lathe-work  than  any  work  of  the  shop. 
Standard  reamers  are  provided  which  are  used  to 
ream  holes  after  boring,  to  produce  a standard  hole. 
Standard  plugs  and  collars  are  kept  in  the  tool-room 
which  conform  with  the  reamers  in  size.  The  workmen 
use  the  plugs  to  compare  with  size  of  the  work,  and 
the  collars  (called  gauges)  to  make  the  final  test  of 
size. 

The  cutting  speed  varies  slightly  with  different 
metals  and  depths  of  cut.  Fifteen  to  twenty  feet  per 
minute  will  be  the  limits.  Very  often,  time  can  be 
saved  by  an  increase  of  the  feed  rather  than  the  speed 
of  the  metal.  For  1"  round  iron  and  steel  use  the 
slowest  single- gear  speed.  Close  observers  soon 
learn  to  judge  the  speed  by  the  passing  metal.  Spots 
should  be  easily  seen. 

The  lathes  are  oiled  once  a week,  by  a man  in 
charge.  The  student  is  expected  at  the  start  of  each 


54 


MAl^UAL  OF  INSTRUCTION  IN 


day  to  clean  ofif  the  V slides  for  the  carriage,  .and  odl .. 
them  with  machine  oil;  then  see  that  the  change 
gear  are  disengaged  and  the  lead-screw  free  from  the 
half-nut.  Turn  the  lathe  by  hand  to  be  sure  of  no 
other  trouble.  Be  careful  in  the  use  of  feeds  to  be 
sure  there  are  no  obstructions.  Never  stop  and  leave 
a lathe  with  a feed  connected.  When  stopping  a cut, 
always  stop  the  feed  before  stopping  the  lathe. 

Use  lard  oil  sparingly  v/hen  cutting-off,  drilling 
holes  and  cutting  threads. 

Use  water  on  wrought-iron  and  steel  to  take  a 
smooth  cut;  add  2 grains  of  sal-soda  to  keep  it  from 
rusting. 

Nothing  need  be  used  on  a roughing-cut  unless 
it  is  very  heavy,  and  then  water  is  applied  to  keep 
the  tool  from  smoking. 

Never  use  lard  oil  for  turning. 

The  cutting- off  tool  should  not  be  used  at  a 
greater  distance  from  the  chuck  than  1^  times  the 
diameter  of  the  iron  cut.  The  metal  is  liable  to  bend 
at  a greater  distance.  ^ ^ 

The  only  tools  that  must  be  placed  level  with 
the  center  are  those  that  go  to  the  center,  like  the 
cutting-off  and  side  tools.  The  diamond-point  should 
be  above  the  center  to  give  it  a freer  cutting  angle 
(called  “more  rake”)  and  to  make  it  nearly  tangent  to 
the  metal  and  lessen  the  liability  of  breaking  the 
point  off.  However,  should  the  tool  become  tangent,  , 
the  tool  will  crowd  away  and  then  dip  in  again,  malaF 


FORGE  MAGEF^E  WORK. 


rs 


ing  the  surface  corrugated  at  irregular  intervals.  In 
grinding,  be  careful  to  keep  the  tool  in  its  original 
shape  so  it  can  be  placed  above  the  center  and  not  be 
tangent;  grind  the  cutting  edge  as  shown  in  Fig.  17. 

Every  student  must  use  his  own  tools.  When 
they  are  used  up,  forge  them  again. 

No.  1.  I.  Put  on  the  4>jaw  chuck;  chuck  a bar 
of  1"  Rd,  iron  allowing  1^"  to  project.  After  grind- 
ing the  cutting-off  tool  as  in  Fig.  18,  practice  cutting 
off  the  rod  into  pieces  long.  Use  lard  oil,  drop 
at  a time,  every  third  turn,  but  in  the  proper  place. 
See  that  the  disks  are  cut  true.  Have  them  inspected. 

II.  Cut  down  the  bar  as  small  as  possible  with 
one  cut  of  the  diamond  point.  Using  the  self-feed;  cut 
off  two  disks  from  the  cylinder  thus  turned;  they 
should  be  reduced  to  at  least.  Inspection. 

III.  Cut  off  stock  for  No.  2,  long. 

IV.  Chuck  this  piece  again;  drill  centers  in  the 
ends.  First  start  a countersink  for  the  drill  by  use 
of  a special  tool  on  the  tool-board.  Second,  drill 
a hole,  deep.  Third,  countersink  60®,  with 
a half-center,  to  diameter. 

Noth. — In  IV.  use  the  fastest  speed.  The  chuck 
jaws  can  be  set  close  by  the  rings  on  the  face,  and 
still  closer  by  trueing  up  after  starting  by  the  mark 
of  chalk.  When  once  set,  they  need  not  be  changed 
if  only  two  jaws  are  moved.  The  independent-jaw 
chuck  is  used  for  lathes,  because  it  can  be  screwed 
very  tight,  also  it  is  adjustable  to  the  unevenness  of 


56 


MAmAL  OF  INSTRUCTION  IN 


the  work.  In  this  work  tighten  it  all  you  can;  it 
will  not  break.  If  the  work  is  loose  in  the  chuck? 
there  is  trouble  at  once. 

Study  ypuf  work;  be  deliberate. 

No.  2.  In  preparing  the  lathe  for  this  work, 
remove  the  cfiuck  by  using  the  back-gear  to  give 
power,  and  a block  of  wood  between  a jaw  and  lathe 
bed.  The  single -gear  /can  then  be  replaced  on  the 
slowest  speed  and  the  lathe  run  backwards.  Hold 
the  chuck  firmly  by  hand  to  keep  it  from  striking 
the  bed..  Do  not  turn  the  chuck  over  on  its  back, 
for'  the  chips  will  fall  into  the  thread  and  cause 
trouble.  Start  the  face-plate  by  hand;  never  while 
the  lathe  is  running. 

The  center  hole  must  be  cleaned  out  and  the 
sleeve  cleaned  inside  and  outside,  and  the  center 
cleaned.  Dirt  in  these  places  causes  the  center  to 
be  out  of  true,  and  the  work  to  be  excentric,  which 
will  be  noticed  where  the  cuts  meet. 

The  centers  are  all  kept  true  by  grinding  and 
will  be  true  in  their  place  when  properly  cared  for. 
The  live  center  is  tested  while  running,  with  the 
work  in  place  withouf-a  dog;  hold  it  from  turning  by 
hand  and  put  a tool  close  to  it;  if  a movement  is  not 
observed,  it  is  true. 

Strictly  speaking,  it  is  impossible  to  keep  this 
center  perfectly  true  and  yet  remove  it  at  will  The 
lathe-hand  who  knows  this  can  so  do  his  work  * that 

k 


57 


FORGE  AND  MACHINE  WORK. 


the  effect  will  not  be  injurious  if  the  excentricity  is 
but  little. 

The  tail-stock  center  is  not  always  left  just 
where  it  should  be,  but  each  student  is  responsible 
for  his  own  work.  A mark  is  placed  on  the  slide  to 
assist  in  setting  it  straight,  but  the  surest  method  is 
to  observe  the  results  of  the  tool  on  the  work.  After 
taking  a cut,  draw  the  tool  across  and  scratch^  line 
to  see  that  the  tool  has  cut  properly,  then  caliper  the 
work  to  test  it  for  straight.  To  move  the  center, 
loosen  the  main  bolt  before  adjusting  the  screws. 
After  a straight  trial  cut  has  been  taken,  the  lathe  is 
ready  for  the  finishing  cut.  This  is  not  as  difficult 
as  might  be  expected. 

Always  make  these  tests  before  starting  your 
work  of  the  day;  running  the  tool  along  close  to  a 
finished  job  will  be  all  that  is  necessary,  generally 
speaking. 

I.  With  the  work  on  centers,  dog  in  place,  face 
up  the  ends  with  the  side  tool  (Fig.  19)  making  the 
1 mgth  6".  To  cut  off  the  burr  that  is  left  close  to 
the  center,  either  back  off  the  center  to  make  room 
for  the  side  tool  or  put  the  60°  half-center  in  as  a 
center,  which  will  allow  the  tool  to  do  the  desired 
work. 

RuIvK. — The  ends  must  always  be  faced  to  the 
length,  the  first  thing,  on  every  piece  of  work. 

Do  not  attempt  to  do  any  work  on  centers  with- 


58 


MAlSfVAL  OF  INSTRUCTION  IN 


out  facing  the  ends  on  centers  properly  drilled;  the 
ends  cannot  be  faced  true  in  the  chuck. 

II.  ' Take  roughing  cut  to  diameter. 

The  diamond  point  should  have  a flat  on  the 
point  about  wide  to  prevent  cutting  ridges. 

III.  Turn  the  shaft  to  using  soda  water 
for  a finish-  Compare  the  size  with  the  plug  or 
gauge,  kept,  in  tool-room,  allowing  about  .001"  for 
polishings  Do  not  try  to  take  a number  of  very 
fine  cuts,  r 

IV.  Place  the  belt  on  the  fastest  speed  and 
loosen  the  center.  Polish  by  holding  the  emery- 
cloth  in  the  hand;  caliper  often  to  find  where  polish- 
ing is  needed  to  allow  the  collar  gauge  to  fit  neatly. 
Inspection. 

Noth. — No  filing  is  allowed.  It  is  a failing  of 
most  students  to  polish  too  much  where  not  needed. 
In  case  the  first  piece  is  spoiled,  the  chuck  need  not 
be  ^replaced  to  cut  off  a new  piece.  Saw  it  off  and 
locate  the  centers  by  a punch,  test  by  chalking  on 
centers,  then  drill,  on  centering  machine  or  drill 
press.  This  way  is  the  most  practical  way  of  center- 
ing where  stock  is  to  be  removed. 


FORGE  A.VZ)  MACE  IN  E WORK, 


f9 


No.  3.  (Fig-  34.)  Stock  used,  No.  2. 

This  exercise  is  intended  to  give  the  student 
practice  in  close  measurement  and  detail  work  from 
a sketch.  None  but  first-class  work  will  be  accepted. 

I.  Turn  as  in  No.  2 to  fit  gauge.  Inspection. 

II.  Round  the  end  by  changing  the  position  of 
the  side-tool,  leaving  a series  of  small  flats  that  can 
be  easily  polished  off.  Use  water.  This  can  be 
done  by  eye  only;  the  curve  is  regular,  not  a round 
corner. 

III.  Cut  out  groove  roughly  with  the  diamond 
point;  then  finish  the  part  with  cutting-off  tool, 
the  face  with  a left-hand  side-tool,  and  the  fillet  with 
a round  nose  tool.  Make  the  fillet  so  a rod  will 
lie  in  the  proper  place. 

In  finishing  cylinders,  tapers  or  a face,  a tool 
point  carried  by  the  lineal  movement  of  the  slides 
gives  the  best  results.  But  when  roundings  or  fillets 
are  made,  the  operator  must  depend  upon  the  shape 
of  the  tool  point  and  the  sight  to  get  the  required 
shape. 

IV.  Place  the  dog  on  the  finished  end  with 
brasses  which  are  in  tool-room.  Set  the  lathe  ap- 
proximately for  the  desired  taper  by  pleasuring  the 
offset  of  the  tail-stock.  This  offset  is  figured  by  use 
of  similar  triangles.  Draw  line  CB'  through  the 
center  and  parallel  to  the  taper  side.  Then  AB  will 
equal  and  A'  B'  is  the  desired  measurement. 
Then  CA  : CA'  ::  AB  : A'B';  substituting  we  have 


60 


J/iyPAL  OF  INSTRUCTION  IN 


^/g/_^A><_A^_|«  moving  the  tail-stock 

w A 

and  roughing  off  the  taper,  before  finishing,  set  the 
tool  at  the  end  and  cut  to  the  right  size.  Loosen 
the  center  and  move  the  tool  over  past  the  line  AB, 
replace  center,  and  notice  the  position  of  the  tool 
when  at  AB.  Move  the  tail-stock  if  necessary  and 
try  again.  The  latter  method  is  the  surest  and  can 
always  be  used.  It  is  modified  by  placing  a scale 
between  the  tool  and  the  work  as  a constant,  re- 
moving or  replacing  at  will,  without  loosening  the 
center. 

A special  gauge  is  provided  for  a final  test  for 
taper  and  size.  To  test  a taper,  put  on  three  longi- 
tudinal lines  with  chalk,  and  exert  a side  pressure 
while  turning  about  one-third  around,  back  and  forth. 
The  chalk  will  not  be  rubbed  off  all  around,  where 
the  fit  is  loose.  Inspection.  ^ 

Note. — Unless  the  tool  for  turning  taper  is  level 
with  the  center,  the  results  will  not  be  as  expected. 

V.  Polish  at  high  speed,  keeping  all  the  corners 
distinct.  The  round  end  can  be  polished  crosswise, 
by  hand,  to  remove  the  ridges,  then  polished  on 
centers. 


[m: 


¥-~ 


.JiT. 


FORGE  AND  MACHINE  WORK. 


61 


. No.  4.  (Fig.  35.)  Stock  used  is  ^ Rd.  Machin- 
ery Steel. 

This  exercise  is  given  to  show  the  spring  of  the 
metal  away  from  the  tool. 

In  turning  No.  3 the  work  was  quite  stiff  and  no 
diflSculty  of  this  kind  was  experienced  except  by 
close  observation;  and  too  often  the  tool  is  ground 
very  wide  on  the  point  in  order  to  make  it  cut 
smooth.  A wide  tool  is  a detriment  to  true  work;  it 
increases  the  amount  of  linear  pressure  and  causes 
the  work  to  spring  away  from  the  tool. 

In  No.  4 the  diamond  point  is  used  and  must  be 
ground  so  that  it  has  only  flat  surface  on  the 
point,  and  even  then  the  shaft  will  spring  away  from 
the  tool  and  the  tool  must  be  fed  in  by  hand  to  keep 
the  shaft  parallel. 

Take  the  front  corner  of  the  tool  off  with  an  oil- 
stone; have  a sharp  cutting  edge. 

I.  Saw  the  stock  off  and  drill  the  centers  after 
they  are  located  to  suit  the  bends  that  may  exist  in 
the  shaft.  It  is  better  to  have  it  true  in  the  center 
than  on  the  ends;  the  ends  can  easily  be  turned  while 
the  middle  will  spring  away  from  the  tool  and  make 
it  hard  to  be  turned  true. 

II.  Remember  to  face  the  ends. 

III.  Take  two  roughing  cuts  from  both  ends, 
leaving  to  finish.  Follow  the  tool  with  calipers 
and  feed  the  tool  in  as  the  shaft  springs  away. 


62 


MANUAL  OF  INSTRUCTION  IN 


IV.  Regrind  the  tool  and  take  the  finish  cut  in 
the  same  way,  using  soda-water. 

V.  Use  a 10"  mill  file  to  smooth  off  the  steps 
or  irregularities.  ‘‘Speed  up”  and  loosen  the  center 
and  oil  it.  Hold  the  file  to  point  10  degrees  to  the 
right  of  a right  angle,  and  push  it  slowly  ahead. 

^Touch  the  shaft  lightly  and  evenly.  Galiper  often. 
Filing  is  not  done  to  remove  metal  that  could  be 
turned;  it  is  done  to  smoothen  work.  Yet  it  is  very 
impractical  and  there  is  liability  of  filing  the  shaft 
out  of  round. 

VI.  Polish  to  fit  gauge,  and  measure  the 
center  part. 

Noth. — Finish  without  filing  if  possible.  The 
speed  for  this  is  faster  than  that  for  No.  2. 

The  following  rest  is  used  to  follow  the  tool,  but 
is  not  needed  at  this  time.  It  is  especially  adapt- 
ed to  cutting  square  top  thread,  after  the  shaft  is 
finished. 


/>>  S6 


FORQE  AND  MACHINE  WORK. 


63 


Diameter 
of  Screw. 

Number  of  Threads 
per  Inch. 

A 

B 

¥' 

11 

¥' 

V' 

¥' 

11 

¥' 

n" 

¥' 

11 

¥' 

n" 

¥' 

11 

1// 

2 

n" 

¥' 

11 

n" 

¥' 

11 

1" 

21"- 

1// 

2 

12  . 

¥' 

%" 

1// 

12 

W'  . 

¥' 

12 

¥' 

11" 

1// 

12 

1// 

o 

n" 

¥' 

12 

V' 

2 " 

7 // 
16 

14 

¥' 

¥' 

7 // 
16 

14 

¥' 

IV' 

1 6 

14 

¥' 

U" 

7 // 
16 

14 

¥' 

If" 

¥' 

16 

i" 

¥' 

¥' 

16 

V' 

1" 

¥' 

16 

¥' 

1 

¥' 

16 

¥' 

U" 

16 

¥' 

11" 

No.  5.  (Fig.  36.)  Cutting  thread  with  a single 
tool  in  the  lathe  is  the  only  way  to  get  the  work  true, 
and  it  is  often  just  as  necessary  to  have  true  threads 
on  a piece  of  work  as  to  have  the  remainder  true. 
The  student  should  be  able  to  cut  thread  with  ease 
and  certainty;  he  is  expected  to  make  18  of  the 
screws  given  in  the  list  selected  by  the  instructor, 
and  should  be  able  to  cut  one  perfect  screw  every 


64 


MAmAL  OF  INSTRUCTION  IN 


hour  without  spoiling  any.  These  are  standard 
screws  with  60-degree  threads,  which  should  not  be 
quite  sharp;  the  screw  is  turned  a little  small  to 
allow  for  a slight  flat  on  top;  small  for  a screw 
is  about  right. 

The  smooth  part  ‘"A”  is  made  the  size  of  the 
threads  also.  The  head  is  made  of  square  iron  or 
bright  rods,  larger  than  the  size  of  the  screw. 
The  ends  are  slightly  beveled  to  preserve  the  threads. 

Use  the  chuck  and  keep  the  work  up  close,  put 
the  head  of  the  long  screws  in  the  chuck  and  draw 
them  out  to  cut  off  behind  the  head.  If  a center  is 
used,  be  careful  to  drill  the  center  properly. 

See  that  the  head  is  faced  square. 

Grind  the  thread  tool  by  the  center  gauge,  a little 
sharper  if  anything.  Set  the  tool  by  the  gauge  and 
level  with  the  center. 

In  placing  the  change  gears  in  position,  make  all 
screws  secure  and  yet  allow  the  idler  to  have  play  so 
you  are  certain  the  teeth  are  not  crowded  together. 

Use  lard  oil  in  cutting.  Withdraw  the  tool  be- 
fore stopping  or  reversing  the  lathe.  Replace  it  again 
before  starting  the  cut.  The  cross-feed  handle  can 
be  replaced  to  its  former  position  by  observation  of 
the  marks  on  the  micrometer.  Adjust  the  desired 
depth  of  cut  with  the  compound  rest. 

When  cutting  heavy  at  first,  the  tool  lags  back 
longitudinally  by  reason  of  the  strain,  so  that  the 
front  side  only  will  cut  when  taking  light  finishing 


FORGE  AiYD  MAGHIEE  WORK, 


65 


cuts.  This  leaves  the  one  side  of  the  thread  rough 
and  the  tool  must  be  moved  by  a light  blow  on  the 
side,  so  it  will  cut  on  both  sides. 

In  cutting  long,  slim  screws,  it  is  best  to  move 
the  tool  and  cut  on  one  side  at  a time. 

In  this  work  the  ends  will  be  largest,  due  to  the 
spring. 

The  screw  gauge  should  fit  close  and  turn  by 
hand. 

File  off*  the  burrs  at  both  ends. 

The  head  can  be  rounded  by  slhnting  the  tool 
after  the  head  is  partly  cut  off*.  Put  on  water  for  a 
finish  just  as  it  drops  off*. 

Fig.  37  shows  a method  for  rounding  the  heads 
where  the  first  is  not  successful.  The  holder  is  made 
in  the  chuck  each  time  it  is  used  and  should  not  be 
removed  till  all  the  screws  are  finished.  A tool  can 
be  ground  to  round  off  the  head  in  one  operation. 

The  commercial  standard  for  the  number  of 
thread  per  inch  is  as  follows: 


bize  ol  Screw 

5 

1 6 

1 

I 7 
T6 

1 * 

! * 

% 

i 

Thread  per  iuch. 

20 

18 

16 

|14 

|l2' 

'll 

10 

9 

8 

Sometimes  13  threads  per  inch  are  used  for 
screws  and  bolts. 


Common  bolts  are  made  ^2!'  above  the  size  be- 
cause of  the  roughness  of  the  iron.  So  there  is  a 
distinction  between  bolt  taps  and  hand  taps.  All 
screws  are  made  for  the  hand  tap  size,  which  is  even 


66 


MANUAL  OF  INSTRUCTION  IN 


size.  The  hardened  and  polished  nuts  used  in  ma- 
chine construction  are  hand  tap  or  standard  size. 
The  blanks  are  cold  punched.^ 

No.  6.  It  is  here  intended  to  give  a problem  in 
thread-cutting  similar  to  that  which  is  found  in  prac- 
tice, and  show  one  of  many  such  schemes. 

Pipe=cutting  can  be  done  to  an  advantage  in  an 
engine  lathe;  by  chucking  one  end  of  the  pipe  on  the 
inside,  so  that  threads  can  be  cut  on  the  outside; 
allowing  the  long  end  to  extend  out  over  the  lathe, 
resting  on  rollers  or  blocks,  which  are  firmly  fastened 
to  the  lathe. 

The  student,  however,  will  be  given  a pipe  that 
is  of  convenient  length.  The  pipe-center  can  be  used 
to  support  the  end. 

^ Chuck  the  pipe  as  above  mentioned,  leaving 

34^'' or at  the  end  thread  tool.  Cut  off*  a 

nipple  to  length  given'^by  th%instructor.^ 

comgpund  rfetdo  cut  taper  to  1 
ft.  :on  the  end  in  the  chuck,  ..and^.  turn  the  end  to 
meastire  one  of  the  following  sizes,  2i|",  4|J", 

which  represent  the  various  sizes  of 
pipe.  Be  cautious  in  measuring  not  to  spring  the 
calipers.  The  cut  should  be  run  out  until  it  cuts 
half  of  the  black  away. 

When  setting  the  compound  rest,  measure  from 
the  side  to  a straight-edge  held  up  from  the  edge  of 
the  carriage.  Set  it  to  6". 

Take  notice  of  the  speed. 


FORGE  Als^D  MAG  EIRE  WQRK. 


67 


III.  The  compound  rest  is  only  used  to  give 

the  pipe  the  desired  taper  .a,nd  can  not  be  used  in 
cutting  threads.  , 

Cut  the  thread  by  starting  the  tool  in  while  the 
lathe  is  turning,  and  gradually  feed  in  as  it  advances 
along  the  taper,  until  the  thread  is  sharp  and  evenly 
cut.  Use  one  side  of  the  tool  at  one  time  while  fin- 
ishing. File  off  burrs.  All  pipe  above  2"  have  8 
threads  per  inch. 

Do  not  leave  unfinished  work  in  the  chuck  until 
the  next  shift  come  on. 

IV.  Cut  the  thread  on  the  other  end  in  the  sahte'"' ' ^ 
way.  Start  the  lathe  on  single  gear  and  set  it 

by  eye.  The  thread  can  be  excentric  slightly,  but 
must  be  true  longitudinally.  Set  the  end  in  the 
chuck  first,  then  strike  it  with  a hammer  to  true  up 
the  thread. 

Notks  on  Cutting  Thread. — When  the  lead- 
screw  has  the  same  thread  per  inch  as  the  thread  to  be 
cut,  the  lathe  need  not  be  reversed  and  the  tool  will  be 
right  at  any  place.  It 'can  be  returned  by  use  of 
the  half-nut.  When  the  thread  on  both  are  not  the 
same,  the  tool  can  be  moved  just  1"  or  2"  in  this  way. 
When  both  threads  can  be  divided  by  2,  then  the 
tool  will  come  right  every  along  the  lead-screw. 

To  do  this  the  lathe  must  be  stopped  and  the  distance 
measured,  but  it  soon  becomes  an  easy  method  and  is 
very  useful  in  cutting  a long  threap  at  a slow  speed. 

Figuring  the  number  of  teeth  in  the  gear  on  the 


68 


MAl^VAL  OF  INSTRUCTION  IN 


Spindle  and  on  the  lead  screw  is  a very  simple  opera- 
tion. They  are  inversely  proportional;  t.  e.y  the 
spindle  gear  is  to  the  lead- screw  gear  as  the  number 
of  threads  per  inch  on  the  lead-screw  is  to  the  num- 
ber of  threads  to  be  cut.  The  unknown  gear  is  usu- 
ally the  one  on  the  lead-screv/.  When  compounded 
gears  are  introduced  between  these  two  gears,  the 
drivers  are  multiplied  together  and  considered  as  a 
spindle  gear  and  the  driven  as  a lead-screw  gear. 
When  one  or  a series  of  idlers  are  placed  between,  no 
change  is  made  in  the  proportion. 


No.  7.  (Fig-  38.)  Curve  Work,  Lathe  Handle. 
Made  from  Machinery  Steel  stock,  on  centers.  Se- 
lected by  the  instructor. 

The  shape  of  part  A can  be  taken  from  the  lathe 
handle  in  use. 

I.  Saw  off  and  center  the  stock.  Face  the  ends 
to  right  length. 


FORGE  AND  MACHINE  WORK. 


69 


II.  Take  roughing  cut  all  over,  leaving  plenty 
for  the  dog  on  D. 

III.  Locate  and  turn  places  on  handle  as  points 
to  turn  the  curve  to.  Use  a broad  tool  to  finish  the 
convex  part,  the  ridges  left  can  be  filed  off. 

Use  a hand  tool  or  scraper  on  the  concaved  part; 
put  up  a rest  (a  tool)  and  turn  at  the  same  speed  as 
other  tools. 

IV.  After  all  the  ridges  are  removed,  polish,  by 
use  of  emery-cloth  on  a stick  used  as  a lever  over  a 
rest.  Keep  the  emery  moving  to  avoid  cutting  rings. 
Do  not  put  on  fine  cloth  until  all  the  marks  are  re- 
moved. 

Note. — Leave  D ^^2^^  above  the  size  and  unfin- 
ished, to  be  fitted. 

None  except  first-class  work  will  do. 


70 


MANUAL  OF  INSTRUCTION  IN 


No.  8.  (Fig-  39.)  The  object  of  this  exercise  is 
the  study  of  cutting  special  thread,  both  inside  and 
outside.  Also  of  details  which  are  shown  in  the 
sketch  and  not  indicated  by  measurement. 

The  stock  is  1^"  Rd.  Machinery  Steel  and  a cast- 
iron  nut.  Sometimes  scraps  are  used. 

This  work  must  be  neatly  done;  all  the  points 
mentioned  in  the  previous  work  must  be  observed. 

Use  the  back-gear  and  take  large  cuts  where  pos- 
sible; have  the  chips  curl  up  nicely. 

Make  your  own  thread  tools  out  of  stock  from 
the  tool' room.  File  it  to  its  exact  size  and  shape, 
after  forging.  Temper  to  dark  straw  without  scal- 
ing it  and  it  will  be  ready  for  cutting.  Give  special 
attention  to  the  clearance  slant.  Make  it  very  short; 
a long  tool  springs  out  of  time  and  makes  an  irregu- 
lar thread. 

Cut  the  space  .005"  wider  than  the  thread.  The 
sketch  at  D shows  the  tool  and  clearance  to  allow. 
AB  represents  the  circumference  of  the  screw,  BC 
the  travel  of  the  tool  in  one  turn,  AC  shows  the  slant 
of  the  thread  at  the  cutting  edge. 

Keep  enough  metal  on  the  ends  of  your  work  so 
the  dog  can  be  used  without  brass.  If  your  dog 
slips  in  cutting  the  thread,  the  tool  will  be  broken; 
have  everything  firm. 

Cut  square  thread  with  light  cuts  so  the  sides 
will  be  true  and  smooth.  Finish  one  thread,  then 
change  the  half-nut  of  the  lead-screw  and  cut  the 


FORGE  AED  MAGEIlS^E  WORK, 


next;  see  that  the  tool  is  central  before  cutting. 
Measure  the  depth  with  calipers  wdth  thin  points. 

As  the  nut  will  be  the  first  inside  work  of  the 
student,  it  is  well  to  mention  a few  things  about 
chuck  work  that  will  apply  to  all  work  of  this  kind. 
First:  True  up  the  work,  in  the  chuck,  by  the  part 

not  finished,  or  that  has  but  a little  stock.  Second: 
Do  the  heavy  cutting  all  over  the  parts  to  be  turned 
while  in  this  position,  before  finishing  any  part. 
Third:  Do  not  remove  the  work  from  the  chuck 

until  some  parts  are  finished  that  can  be  used  to  hold 
the  work  true  again;  /.  e.^  should  the  outside  of  a 
pulley  only  be  finished  when  removed  from  the 
chuck,  it  cannot  be  put  back  in  the  lathe  true  to  bore 
the  hole,  while  if  the  hole  is  finished,  it  can  easily  be 
placed  on  a mandrel  on  centers  to  turn  off*  the  out- 
side. In  No.  8 the  thread,  counterbore  and  face 
must  be  finished  before  removing  ft  from  the  chuck. 
Then  it  is  placed  on  the  screw  and  finished  outside. 
Fourth:  Take  off  the  sand  with  a round  nose  tool 

before  using  a drill  or  finishing  tool.  Fifth:  Drills 

may  be  used  to  remove  metal  from  the  holes,  but 
the  boring-tool  must  be  used  to  make  the  hole  true 
before  reaming  to  standard  size.  When  holes  are  a 
special  size,  like  No.  8,  the  reamer  cannot  be  used, 
but  must  be  bored  to  the  size  with  measurements 
carefully  taken  with  calipers.  Reamers  should  not 
remove  more  than  .01".  It  is  a good  practice  to  set 
the  inside  calipers  to  a gauge  rather  than  a scale. 


72 


MA^^UAL  OF  INSTRUCTION  IN 


In  this  case  the  insides  must  be  set  to  the  out' 
side  thread  calipers,  and  a working  fit  made  before 
starting  to  cut  the  thread. 

Cut  light  with  the  thread  tool;  the  cast  iron  is 
severe  on  the  sharp  corners. 

Practice  nurling  on  a piece  of  scrap  before  at- 
tempting to  do  the  nurling  required. 

Polish  as  usual. 

This  exercise  is  diflScult,  but  can  be  well  made 
b}"  every  student.  It  is  of  great  value  to  the  stu- 
dent and  will  speak  for  itself  when  completed. 


No.  9,  (Fig.  40.)  Exercise  in  making  a drive 
fit,  by  use  of  outside  and  inside  calipers. 

In  the  previous  work  measurements  were  made 
by  comparing  the  size  of  the  work  with  a standard 
gauge  by  use  of  the  calipers  and  collars.  In  this 
case  no  comparisons  are  allowed  and  calipers  only 
are  used.  A hardened  block  of  steel  to  which  the 
fit  is  made  is  kept  by  the  instructor  and  the  size 
must  be  taken  from  it  with  insides,  and  then  the  out- 
sides made  to  fit,  and  the  work  to  the  outsides. 

This  is  an  important  and  very  practical  operation 
and  will  need  close  study. 

I.  Set  the  insides  in  the  hole  so  carefully  that 


FORGE  AND  31  AC  BINE  WORK. 


73 


moisture  on  their  points  could  be  detected  by  feel- 
ing. Keep  one  point  still  while  moving  the  other 
lengthwise  and  crosswise  until  the  exact  diameter  is 
found.  Do  not  spring  the  calipers  together  by  hold- 
ing too  tight. 

II.  Hold  one  point  of  each  calipers  together 
and  adjust  the  hairspring  until  a slight  contact  is 
made  on  the  largest  size  found  on  the  insides.  Hold 
one  leg  only,  to  avoid  springing.  Do  not  lay  them 
down  to  do  this;  the  largest  place  can  not  be  found 
in  that  way. 

III.  Use  a scrap  piece  of  steel  and  turn  it  in 
the  chuck  like  the  sketch,  to  a drive  fit  with  a hand 
hammer.  Leave  the  surface  as  smooth  as  the  tool 
will  make  it,  and  straight.  The  diamond-point  will 
do  all  the  cutting.  By  moving  it  back  and  forward 
lengthwise,  both  ends  can  be  made.  The  points  are 
merely  for  convenience  in  driving. 

The  instructor  will  try  the  fit.  Three  trials  will 
be  given.  Most  students  need  but  two  trials. 

Notes. — In  repair  work  the  above  method  is 
often  the  only  one  possible,  and  yet  not  every  work- 
man can  make  a good  fit  at  will. 

To  those  who  inquire  as  to  the  amount  to  leave 
for  a drive  fit,  the  writer  will  say:  Make  it  the  ex- 

act size;  when  a work  fit  is  made,  let  the  insides  be 
slightly  loose,  in  the  hole.  For  a shrink  fit,  allow 
just  enough  to  make  it  impossible  to  drive.  Driving 
cuts  off  the  metal,  but  shrinking  is  to  enter  the  shaft 


74 


MAl^UAL  OF  INSTRUCTION  IN 


loosely  while  the  hole  is  expanded  by  heat»  and  no 
metal  is  lost;  the  result  is  a very  tight  fit.  Often  a 
mistake  is  made  by  leaving  too  much  for  a shrink  fit> 
which  strains  the  metal  nearly  to  its  elastic  limit. 

This  completes  the  exercise  work,  which  usually 
occupies  two  years. 

The  student  is  now  given  parts  of  work  that  is 
put  in  some  machine  or  tool  which  is  in  process  of 
building.  The  following  are  some  things  that  have 
been  built  from  the  rough  in  this  way:  An  8"xl0" 

engine;  16"x6  ft.  engine  lathes;  20"  drill  presses;  a 
16"  shaper;  12"  emery  grinders  and  countershafts;  a 
50,000-pound  transverse  testing  machine.  All  of 
these  are  in  use  here.  Much  apparatus  has  been 
made  for  the  various  laboratories. 

The  cast-iron  parts  and  drawings  are  given  to  be 
machined  and  fitted  up.  All  the  machine  tools  are 
now  used  as  the  work  is  carried  on  by  the  student. 

It  is  impossible  to  give  the  needed  instruction 
here,  but  a few  suggestions  are  all  that  can  be  com- 
prehended until  the  actual  work  is  done.  The  writer 
has  found  that  when  the  exercises  have  been  com- 
pleted, the  student  will  be  more  careful  and  handle 
other  machine  tools  with  the  judgment  necessary  to 
enable  him  to  be  trusted  with  work  of  the  above 
sort. 

The  following  are  a few  general  instructions: 

I.  Turn  everything  on  centers  where  it  is  pos- 


FORGE  A.VD  MACHINE  WORK. 


75 


sible,  leaving  good  centers  in  the  work  when 
finished. 

II.  In  taking  longitudinal  measurements,  start 
from  a finished  face  or  center  line,  just  as  you  do  in 
making  the  drawings. 

III.  Do  not  file  cast  iron  to  prepare  it  for  pol- 
ishing; the  file  scratches.  A broad-tool  finish  is  not 
desirable  for  polishing.  Do  as  much  as  possible  with 
a well-formed  pointed  tool. 

IV.  Hard  cast  iron  can  best  be  turned  or  planed 
with  self-hardening  steel,  ground  round  or  nearly 
thread  tool  shape,  placed  slightly  below  the  center. 

V.  Use  a driver,  and  not  a dog,  on  large  turn- 
ing, such  as  pulleys. 

VI.  Small  keyseats  are  often  cut  in  the  lathe 
by  moving  the  tool  by  the  hand  gear  while  it  is  held 
in  the  tool  post.  Large  ones  are  cut  on  the  planer 
or  shaper.  The  shop  equipment  does  not  consist  ot 
a keyseater. 

VII.  All  lathes  are  provided  with  large  face- 
plates with  slots  and  holes  for  bolts.  These  are  used 
when  work  is  bored  or  turned  true  with  a face  which 
has  been  finished  elsewhere.  Crank  boxes  for  en- 
gines are  bored  last  of  all.  The  strap  is  bolted  to 
the  face-plate  on  parallel  strips. 

VIII.  The  milling  machine  is  provided  with 
chuck  and  center  to  hold  work  much  the  same  as  in 
a lathe.  A mandrel  is  provided  for  the  spindle  with 
bushings  and  a square  thread  nut  to  use  in  holding 


76 


MANVAL  OF  IX8TRUCTI0N  IN 


gears.  A vise  is  used  on  small  work  and  keyseat-^ 
ing  shafts. 

All  work  done  by  the  milling  machine  must  be 
so  designed  that  a revolving  cutter  of  set  pattern  can 
be  used,  which  must  not  be  damaged  in  any  way. 
Hard  cast  iron  or  tool  steel  should  be  machined  else- 
where. The  tool-room  tender  has  the  care  of  this 
tool  and  should  be  consulted  often. 

IX.  The  tools  of  the  planer  or  shaper  are  oper- 
ated much  the  same  as  lathe  tools,  but  the  same  dia- 
mond-point will  not  do  for  both,  owing  to  the  great 
slant  of  a lathe  tool,  which  reduces  the  rake  of  the 
same  tool  in  the  shaper. 

It  is  not  best  to  always  lift  up  the  tool  on  the 
back  stroke. 

Some  difficulty  will  be  experienced  in  holding 
the  work  firmly  and  true  in  the  chuck-vise  of  the 
shaper  and  planer.  The  jaws  will  spring  when 
forced,  and  some  personal  instruction  is  needed. 
Parallel  strips  are  often  used  to  hold  the  work  up. 

In  clamping  work  to  the  table  of  any  machine, 
see  that  the  work  touches  the  table  or  a support 
directly  under  the  clamp;  otherwise  it  will  spring,  and 
when  released  it  will  not  be  true. 

Planing  requires  judgment  in  the  depth  of  the 
cut  and  style  of  finish.  Some  parts  can  be  finished 
with  a broad  tool  and  quick  feed,  but  bearing  sur- 
faces must  be  finished  by  a point. 

X.  In  drilling,  always  clamp  a surface  of  the 


FORGE  AND  MACHINE  WORK. 


77 


work,  if  possible,  to  the  table  or  angle  plate,  which 
is  at  right  angles  to  the  table.  Special  instruction 
must  be  given  in  the  use  of  boring  bars  and  special 
drills.  Always  lay  out  the  holes  with  dividers  when 
possible,  and  drill  every  hole  as  true  as  you  can. 
Drill  holes  for  rough  iron  large. 

XI.  True  shafts  can  be  made  on  the  grinding 
machine,  because  both  of  the  centers  are  dead  cen- 
ters. This  is  desirable  for  high-speed  shafts,  such  as 
motors  and  emery  grinder  shafts. 

All  kinds  of  hardened  work  can  be  ground  true; 
hardening  causes  the  metal  to  swell  in  spots,  which 
give  the  work  a change  in  shape. 

The  work  on  the  grinders  is  all  close  work  and 
micrometer  calipers  are  used.  Many  standard  tools, 
reamers,  plugs  and  gauges,  are  made  here. 

Many  machines  and. tools  are  used  which  will 
not  differ  greatly  from  those  mentioned. 


18 


MANUAL  OF  INSTRUCTION  IN 


APPENDIX. 


To  find  the  size  of  drill  to  use  for  a tap:  Try 

the  cutting  end  of  the  tap  in  the  drill  gauge  and 
select  a drill  that  will  not  cut  quite  a full  thread. 

To  guide  a tap  straight  into  a hole  that  has  just 
been  drilled:  Place  the  butt  end  of  a small  drill, 

which  is  pointed,  in  the  press,  and  hold  it  firmly  in  the 
center  of  the  tap  while  it  is  turned  with  a tap-wrench. 
Holes  smaller  than  can  be  tapped  with  perfect 
safety  in  the  lathe  by  allowing  the  drill  chuck  to 
turn  in  the  tail-spindle  as  a guide  and  hold  or  turn 
the  chuck  and  tap  by  hand. 

To  forge  a square  hole  in  the  end  of  a bar  of 
steel:  Drill  a hole  the  circumference  of  which  equals 

the  perimeter  of  the  square  desired;  heat  and  pound 
the  square  bar  round. 

In  shops  where  small  center  drills  can  not  be 
used,  use  a slender,  flat-ended  punch  to  punch  the 
hole. 

Square-pointed  centers  (pyramids)  are  often  used 
in  place  of  half-centers,  and  are  used  to  cut  the 
center  true  when  the  work  is  forced  into  its  proper 
place  by  a tool-rest  while  revolving. 

The  cylindrical  surface  of  work  in  the  lathe  can 
be  divided  into  even  sections  by  using  a tool  to  mark 
the  divisions  and  the  teeth  in  the  main  gear  as  a 
dividing  head. 


FORQE  AND  MACHINE  WORK. 


79 


The  Taylor-White  steel  is  a steel  lately  invented 
that  will  permit  the  cutting  speed  of  150  feet  per 
minute  with  water.  It  is  not  yet  on  the  market.  It 
will  be  used  in  shape  similar  to  our  self-hardening 
steel. 

The  self-hardening  steel  which  is  used  in  tool- 
holders  on  the  lathe  and  planer  can  be  heated  by 
grinding,  but  should  not  be  put  in  the  water  while 
hot. 

The  following  cuts  serve  to  illustrate  and  show 
the  names  of  the  articles. 


THE  WOODRUFF  PATE;nT  SYSTEM  OF  KEYING. 


80 


MAl^VAL  OF  INSTRUCTION  IN 


ThcSizmgfbf  Spur  Gears* 

The  term  ^'diametral  pitch’’  is  used  to  denote  the 
relative  number  of  teeth  in  connection  with  the  diam- 


diameter  at  the  pitch  circle  and  containing  30  teeth  is 
10  pitch. 

The  pitch  diameter  is  two  parts  of  the  pitch  less 
than  the  whole  diameter. 

A wheel  containing  30  teeth  and  of  10  pitch  will 

, / 30  2 \ 30~1~2 Q . - 

be  = o.^  in  diameter  on  the  out- 

side of  the  blank. 

Let  N = Number  of  teeth.  FormuIvA: 


Tabi^e  of  Depth  of  Space  of  Spur  Wheees. 


Pitch  .... 

20 

18 

16 

14 

12 

10 

8 

6 

'5^ 

4 

Depth  in 
Inches.. 

.108 

.120 

.135 

.154 

.180 

.260 

.270 

359 

.431 

.539 

eter  of  a wheel  at  the  pitch  circle.  A wheel  3"  in 


P = Pitch. 

D = Diameter  of  blank. 


I. 


FORGE  AFD  MAGEMe  WORK. 


81 


n 

Laf/fe~Too/  //oo/c(<>f 


i 1 1 

»■  .. 

f-:' 

S/c/e  Too/\^ 

/^/d/rer-Too/  /^o/dcf' 


PivUG  TAP. 


82 


MAltVAL  OF  INSTRUCTION  IN 


Decimals  of  an  Inch  for  Each  l-64th. 


h- 

6l“‘* 

Decimal 

Fraction 

Decimal 

Fraction 

1 

.015625 

33 

.515625 

1 

2 

.03125 

17 

34 

.53125 

3 

.046875 

35 

.546875 

2 

4 

.0625 

1 

18 

36 

.5625 

5 

.078125 

37 

.578125 

3 

6 

.09375 

19 

38 

.59375 

7 

.109375 

39 

.609375 

4 

8 

.125 

i 

20 

40 

.625 

I 

9 

.140625 

41 

.640625 

5 

10 

.16625 

21 

42 

.65625 

11 

.171875 

43 

.671875 

6 

12 

.1875 

3 

TF 

22 

44 

.6875 

1 1 
TF 

13 

.203125 

45 

.703125 

7 

14 

.21875 

23 

46 

.71875 

15 

.234375 

47 

.734375 

8 

16 

.25 

i 

24 

48 

.75 

1 

17 

.265625 

49 

.765625 

9 

18 

.28125 

25 

50 

.78125 

19 

.296875 

51 

.796875 

10 

20 

21 

.3125 

.328125 

A 

26 

52 

53 

.8125 

.828125 

1 3 
1 6 

11 

22 

.34375 

27 

54 

.84375 

23 

.359375 

55 

.859375 

12 

24 

.375 

i 

28 

56 

.875 

25 

390625 

57 

.890625 

13 

26 

.40625 

29 

58 

.90625 

• 27 

.421875 

59 

.921875 

14 

28 

.4375 

7 

30 

60 

.9375 

H 

i 

29 

.453125 

61 

.953125 

1 15 

30 

.46875 

31 

62 

.96875 

31 

.484375 

63 

.984375 

32 

.5 

i 

32 

64 

1 

] 

\ 

V 


FORGE  AND  MACHINE  WORK. 


83 


Weights  of  Square  and  Round  Bars  of  Wrought  Iron  in  Pounds 
per  Lineal  Foot. — Kent. 

Iron  weighing  480  lbs.  per  cubic  foot.  For  Steel  add  2 per  cent. 


Thickness  or 
Diameter 
in 

Inches. 

Weight  of 
Square  Bar 
One  Foot 
Long. 

Weight  of 
Round  Bar 
One  Foot 
Long. 

Thickness  o*“ 
Diameter 
in 

Inches. 

Weight  of 
Square  Bar 
One  Foot 
Long. 

Weight  of 
Round  Bar 
One  Foot 
Long. 

0 

1-16 

.013 

.010 

1 3-4 
13-16 

10.21 

J0.95 

8.018 

8.601 

1-8 

.052 

.041 

■7-8 

11.72 

9.204 

3-16 

.117 

.092 

15-16 

12  51 

9 828 

1-4 

.208 

.164 

2 

13.33 

10.47 

5-16 

.326 

256 

1-16 

14.18 

11.14 

3-8 

.469 

.368 

1-8 

15.05 

11.82 

7-16 

.638 

501 

3-16 

15.95 

12.53 

1-2 

.833 

.654 

1-4 

16.88 

13.25 

9-16 

1.055 

-.828 

5-16 

17  S3 

14.00 

5-8 

1.302 

1.023 

3-8 

18.80 

14.77 

11-16 

1 576 

1 237 

7-16 

19.80 

15.55 

3-4 

1.875 

1.473 

1-2 

20  83 

16  36 

13  16 

2.201 

1.728 

9-16 

21.89 

17.19 

7-8 

2.552 

2.004 

5-8 

22.97 

18.04 

15-16 

2.930 

2.301 

11-16 

24.08 

18  91 

1 

3.333 

2.618 

3-4 

25.21 

19.80 

1-16 

3.763 

2 955 

13-16 

26.37 

20.71 

1-8 

4.219 

3.313 

7-8 

27.55 

21.64 

3 16 

4.701 

3.692 

15-16 

28.76 

22.59 

14 

5.208 

4.091 

3 

30.00 

23.56 

5-16 

5.742 

4.510 

1-16 

31.26 

24.55 

3-8 

6.302 

4 950 

1-8 

32  55 

25  57 

7-16 

6.888 

5.410 

3-16 

33.87 

26.60 

1-2 

7.500 

5.890 

1-4 

35.21 

27.65 

9-16 

8.138 

6.392 

5-16 

36.58 

28.73 

5-8 

8.802 

6.913 

3-8 

37.97 

29.82 

11-16 

9.492 

7.455 

7-16 

39  39 

30.94 

84 


MA'NVAL  OF  IF  STRUCT  10'S 


AREAS  AND  CIRCUMFERENCES  OF  CIRCLES. 


Diam. 

Area. 

Circum. 

Diam. 

Area. 

Circum. 

1 

64 

.000192 

.01909 

1 

2 

15.9043 

14  1372 

1 

3 S' 

.000767 

.09818 

i 

17.7206 

14.9226 

r« 

.U03068 

.19635 

5 

19.635 

15.708 

i 

.012272 

.3927 

i 

21.6476 

16.4934 

A 

.027612 

.589 

23.7583 

17.2788 

I 

.04W87 

.7854 

i 

25  9673 

18.0642 

A r 

Anm99 

.98175 

6 

28.2744 

18.8496 

I 

.110447 

1.1781 

i 

30.6797 

19.635 

re 

.15033 

1.37445 

4 

33.1831 

20  4204 

4 

.19635 

1.5708 

i 

35.7848 

21.2  58 

tV 

.248505 

1.76715 

7 

38.4846 

21.9912 

t 

.306796 

1.9635 

i 

41.2826 

22  7766 

371224 

2.15985 

i 

44.1787 

23.562 

i 

.441787 

2.3562 

i 

4 

47  1731 

24.3474 

1 3 
16 

518487 

2.55255 

8 

50.2656 

25.1328 

i 

.601322 

2.7489 

i 

53.4563 

25.9182 

1 5 

r? 

.690292 

2 94525 

i 

56.7451 

26  7036 

1 

.7854 

3.1416 

1 

60.1322 

27  489 

i 

1.2272 

3 927 

9 

63.6174 

28.2744 

i 

1.7671 

4.7124 

i 

67.2008 

29  0598 

1 

2.4053 

5 4978 

i 

70.8823 

29  8452 

2 

3.1416 

6.2832 

I 

74.6621 

30.6306 

3.9761 

7 0686 

10 

78  54 

31  416 

h 

4.9087 

7.854 

J 

82  5161 

32.2014 

i 

5.9396 

8 6384 

f 

86.5903 

32.9868 

3 

7.0686 

9.4*248 

i 

90.7628 

33.7722 

J 

8.29^8 

10  2102 

11 

95.0334 

34.5576 

9.6211 

10.9956 

i 

99.4<»22 

35.343 

1 

11.0447 

11  781 

4 

103  8691 

36.1284 

4 

12  5664 

12  5664 

i . 

10 1 4343 

36  9138 

I 

14  1863 

13.35 » 8 

12 

113  098 

37  6992 

If-  ■ 





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i 


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